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        .---------------------------.
       | [::] .-------------------. |
       |     |   3.5" FLOPPY      | |
       |     |   1.44 MB          | |
       |     |   [[ metal shutter]| |
       |      '------------------'  |
       |     [notch]            [o] |
        '--------------------------'
    

The floppy disk is the format that refused to die. IBM shipped the first 8″ floppy in 1971. The 3.5″ disk is still manufactured in 2026. That is 55 years of continuous production — longer than VHS, longer than the compact cassette, longer than the CD. Every technology that was supposed to replace it (Zip, SuperDisk, HiFD, CD-R, DVD-RAM, USB sticks) died or faded while the floppy quietly kept spinning in Roland samplers, Brother embroidery machines, CNC lathes, and — until 2020 — the nav database of every Boeing 747-400 still in commercial service.

This museum covers the three generations of the format (8″ → 5.25″ → 3.5″), the superfloppy contenders that tried to succeed it (Zip, LS-120, HiFD), the copy-protection warfare it birthed, and the preservation tools keeping its ghost alive. The Japanese government only banned floppy-based document submissions in 2024. Chuck E. Cheese animatronics ran on them for decades. The format outlived its own successors.

The one-line thesis

Floppies survived on industrial inertia, not nostalgia. A 1.44 MB disk is useless for modern data. It is perfect for the 500 KB firmware image of a 1994 embroidery machine whose manufacturer refuses to ship a USB update. When replacement cost is "$30,000 for a new machine" versus "$1.50 for a blank disc," the floppy wins. That's why you can still buy new-production 3.5″ drives from Chinese OEMs in 2026, why Verbatim HD disks are still stocked on Amazon, and why Greaseweazle and KryoFlux exist to image the physical flux off disks that hold data no one has the source for anymore.

The floppy didn't die because it wasn't supposed to. It became infrastructure. Infrastructure is what you notice only when it finally stops working.

Physical evolution

Three generations, each smaller and more rigid than the last, plus a late-90s swarm of "superfloppy" contenders that all lost.

8″ IBM 23FD — the original (1971)

IBM's 23FD (code name "Minnow") shipped in 1971 as a read-only program-loader for the System/370 mainframe. 8 inches across, single-sided, around 80 KB of capacity. It was never sold as a standalone product — it was a boot-loader medium that shipped inside specific IBM systems. Alan Shugart, working at IBM and later founding his own company, is the name most associated with the format.

8″ Shugart SA800 — read/write (1973)

The Shugart SA800 in 1973 added write capability. Early capacity was around 240 KB single-sided; by the late 1970s double-sided, double-density 8″ disks reached roughly 1.2 MB. The 8″ drive was the standard storage of CP/M machines, early minicomputers, and word-processors like the Wang and the IBM Displaywriter through the early 1980s. Physically enormous by modern standards.

5.25″ Shugart SA400 — the home computer era (1976)

An Wang reportedly sketched the 5.25″ form factor on a cocktail napkin in a Boston bar after complaining the 8″ disk wouldn't fit in a desktop word processor. Shugart's SA400 shipped in 1976 at 110 KB single-sided. The format evolved rapidly:

• Single-sided, single-density: 110 KB (Apple II, TRS-80)
• Single-sided, double-density: 160 KB (IBM PC 5150, 1981)
• Double-sided, double-density: 320–360 KB (IBM PC DOS 2.0, 1983)
• Double-sided, high-density: 1.2 MB (IBM PC/AT, 1984)

The 5.25″ disk dominated the 1978–1988 home computer decade. It was flexible (genuinely floppy) and the sleeve was the only protection against dust and fingerprints. Apple II and Commodore 64 users stacked them in "disk caddies" next to the CRT.

3.5″ Sony — the rigid era (1981–1982)

Sony introduced the 3.5″ floppy around 1981. Unlike its predecessors it was rigid — a hard plastic shell protected the magnetic disc, and a spring-loaded metal shutter covered the read/write window so the disc itself was only exposed inside the drive. Apple's adoption in the 1984 Macintosh made it the dominant PC format by the late 1980s.

• DD (Double Density): 720 KB PC, 800 KB Mac (GCR), 400 KB single-sided Mac
• HD (High Density): 1.44 MB — the canonical "floppy" most of us remember, introduced 1987 with IBM PS/2
• ED (Extended Density): 2.88 MB, introduced by IBM around 1991. Commercial flop (pun intended). NeXTSTEP, IBM PS/2 Model 57, and a handful of others. Failed against cheap CD-ROMs.

3″ Amstrad/Hitachi — the UK oddity (1982)

The Compact Floppy (CF-2) was a 3-inch (not 3.5) format used primarily in UK home computers: the Amstrad CPC, Amstrad PCW, the ZX Spectrum +3, and some Tatung systems. Roughly 180 KB per side, flippable like a cassette. Completely orphaned by the mid-1980s when 3.5″ Sony won the rigid-shell war.

Superfloppy contenders (1994–2001)

By the mid-90s everyone knew 1.44 MB was inadequate. Four contenders fought to be "the new floppy":

• Iomega Zip (1994) — 100 MB, wildly successful at launch, later 250 MB (1998) and 750 MB (2002). Physically distinct cartridge (not a true floppy upgrade).
• Imation/Panasonic LS-120 SuperDisk (1996) — 120 MB, backward-compatible with standard 3.5″ HD disks. The compatibility sounded great on paper; the market disagreed.
• Sony HiFD (1998–99) — 200 MB then 150 MB, also backward-compatible with 1.44 MB. Plagued by reliability issues and launched late; effectively stillborn.
• Iomega Jaz (1995) — 1 GB and later 2 GB, but more of a removable hard drive than a floppy descendant. Sold to creative professionals, not the mass market.

Capacity tiers

Every common capacity you'll find in the wild, smallest to largest. "Sides" and "density" codes are printed on most original sleeves.

File systems by era

The physical disk is the same magnetic surface across eras. The logical formatting on it is wildly different depending on the platform that wrote it — which is why a Mac 800K disk is physically identical to a PC 720K disk but completely unreadable by a standard PC floppy controller.

FAT12 — the universal default

FAT12 (12-bit File Allocation Table, originally from Microsoft's 1977 Standalone Disk BASIC) became the near-universal PC floppy filesystem under MS-DOS. Every 360 KB, 720 KB, 1.2 MB, 1.44 MB, and 2.88 MB PC floppy you ever touched used FAT12. Still supported natively by every version of Windows, Linux, and macOS in 2026. The format is so simple it can be parsed by a few hundred lines of assembly.

Apple GCR — the Wozniak special

Apple II and early Macintosh disks used Group Coded Recording rather than MFM. Steve Wozniak's Apple Disk II controller (1978) was a software-driven bitbanger on a 6502 — it literally encoded and decoded the disk signal in CPU instructions, with no dedicated controller chip. That's why Apple II disks hold more than PC disks of the same size (140 KB vs 160 KB on 5.25″) and why they're unreadable by a generic PC floppy controller. Mac 400K/800K used a variable-rotation-speed GCR scheme that packed more data onto outer tracks — another software-only trick that modern floppy controllers cannot replicate without flux-level hardware.

Commodore 1541 GCR

The Commodore 1541 drive (C64) used its own GCR variant with a dedicated 6502 inside the drive itself. Infamously slow (about 400 bytes per second without JiffyDOS or fastloader cartridges) because the serial bus was throttled — but the actual disc encoding was efficient. 170 KB per side. Flippable disks were standard practice.

Amiga OFS / FFS

The Commodore Amiga shipped with OFS (Old File System) and upgraded to FFS (Fast File System) in AmigaOS 1.3/2.0. Amiga 3.5″ disks use MFM encoding but pack 880 KB onto a DD disc where PCs only fit 720 KB — because the Amiga controller handles the entire track itself rather than relying on controller-chip sector gaps. Unreadable by standard PC drives.

Atari ST — near-FAT12

Atari ST used a slight FAT12 variant on 3.5″ disks — close enough that many ST disks can be read on a PC with the right tool, but the boot sector differs. Most 720 KB ST disks are recoverable by standard imaging tools.

CP/M

CP/M filesystems varied by manufacturer — there was no "standard" CP/M disk format. Kaypro, Osborne, Morrow, Televideo and others each shipped their own sector layouts, making CP/M floppies notoriously platform-dependent. Tools like cpmtools on modern systems ship with a disk-parameter block library for hundreds of known formats.

Format wars (a greatest-hits)

The floppy never really "lost" a format war. It stayed dominant for a specific niche (firmware, boot, small-transfer) long after its successors were assumed to have killed it.

Copy protection wars

The 1980s and early 1990s gave the floppy a second, quieter history: an arms race between software publishers who wanted to stop piracy and crackers who wanted to move the bits anyway. Every weird physical quirk of the floppy format became a copy-protection weapon.

Apple II — RWTS and nibble copies

Apple II games used custom RWTS (Read/Write Track/Sector) routines that deviated from Apple's standard DOS 3.3 or ProDOS sector layout. Programmers would write custom encoding, intentionally damaged sectors, half-tracks, and sectors with non-standard sync bytes. Stock DOS copy tools (FID, Copy II Plus) couldn't reproduce the weirdness. Specialized nibble copiers like Locksmith, Copy II Plus nibble mode, and EDD copied the raw byte stream, not the logical sectors. Each new protection scheme spawned a new version of the copier within weeks.

Commodore 1541 — half-tracks and weak bits

The Commodore 1541 drive could position the head on half-tracks (between the standard tracks) because of its stepping-motor granularity. Games wrote data that spanned multiple half-tracks or intentionally mis-aligned sync marks. "Weak bits" were sectors with unstable magnetic fields that read differently each time — a copy would read them once and reproduce a stable value, failing the protection check. Tools like Fast Hack'Em and Maverick fought back.

Roland sampler disks — sector gaps

Roland S-50, S-550, and W-30 sampler disks used non-standard sector-gap timing, making them unreadable on any generic PC drive even after MFM decoding — a physical-layer protection scheme that survived into the DAW era. Even in 2026, preserving a Roland library requires a flux-level imager (Greaseweazle, KryoFlux) rather than a regular disk copy.

Out-of-band protection: Lenslok, codewheels, manual lookups

When physical disk protection got cracked too quickly, publishers added out-of-band puzzles:

• Lenslok (1985, Elite and others) — a plastic lens that had to be held over the screen to read a distorted code
• Codewheels (Secret of Monkey Island, countless others) — physical rotating cardboard discs mapping symbols to codes
• Manual lookups (Ultima, Starflight, LucasArts games) — "turn to page 47 of the manual and enter the 4th word of paragraph 2"
• Dark-paper printed codes — red/black ink that photocopiers couldn't reproduce

The scene economy

Feature legend

Device cards below use these tags to flag capability and format support at a glance.

Iconic drives

The machines that wrote the format's history. Not a complete catalog — a highlight reel of the ones that mattered, with eBay search links for hunting.

Iconic media brands

The brand on the label genuinely mattered. Cheap no-name disks shed oxide and fail; premium brands from the HD era are still readable in 2026.

The write-protect notch culture

Write-protection is mechanical on floppies — a physical notch or tab that the drive detects optically or with a microswitch. Each format generation inverted the convention of the last.

5.25″ — cover the notch = protected

On 5.25″ disks the write-enable notch is a rectangular cut in the sleeve edge. Covering the notch (with a piece of tape or the silver foil stickers that shipped with every box) made the disk write-protected. No notch at all meant write-protected too — which is how single-sided disks were sold (the back side had no notch, hence the factory wouldn't write to it).

3.5″ — sliding tab, inverted

The 3.5″ shell flipped the convention: open the sliding tab = protected, closed = writable. This caused endless confusion for users moving between the two generations.

The "flippy disk" hack

Early Apple II and Commodore 64 users saved money with the flippy disk: take a single-sided 5.25″ disk (factory-notched on one edge only) and cut a second notch in the opposite edge with scissors or a dedicated tool. Flip the disk over and the drive would now write to the other magnetic surface — doubling capacity. Factory single-sided disks were identical to double-sided disks in magnetic coating; the "single-sided" rating was just which surface passed QC testing. The flippy hack worked reliably on Apple II, C64, and the Commodore 1541 in particular.

Consumer disk notchers

Retailers sold dedicated disk notchers — a pliers-like tool with a rectangular cutout die specifically shaped for the 5.25″ notch. Radio Shack, Computer Shopper catalogs, and every college bookstore carried them through the 1980s. Typical price $3–7. A cultural artifact in its own right.

Zip disk disasters — the "Click of Death"

Iomega's Zip drive launched in 1994 at 100 MB per cartridge and briefly owned the mid-90s superfloppy market. Every graphic designer, every small business, every college student with a poster project carried Zip disks. Apple bundled Zip drives in the beige G3. Then the drives started eating the disks.

What the Click of Death actually was

The "Click of Death" was a failure mode where the drive's read/write head crashed into the cartridge's head-positioning surface, damaging both the drive heads and the cartridge. Once a drive developed the problem, it would damage every subsequent disk inserted. Once a disk was damaged, every subsequent drive it was inserted into risked becoming infected. The failure was contagious through a shared disk.

The class action

Iomega faced a class-action lawsuit in the late 1990s (Tatum v. Iomega, settled 2001) over the defect. The settlement was widely criticized as favoring Iomega. Thousands of dissertations, small-business accounting files, photography portfolios, and academic research datasets were permanently lost. Iomega never fully recovered — they limped through the early 2000s, sold to EMC in 2008, and the brand was absorbed into Lenovo.

Preservation in 2026

The floppy preservation scene is unusually healthy because the hardware problem was solved with FPGA tools that capture the raw magnetic flux rather than trying to decode at the controller level. Flux-level imaging bypasses every copy-protection scheme ever invented and produces archive-grade preservation files.

Greaseweazle — open-source flux reader

Greaseweazle is an open-source USB-to-floppy-drive adapter built around a simple STM32 microcontroller. It captures the raw flux transitions off the drive heads and streams them to a PC, producing .scp (SuperCard Pro) or .hfe format files. Handles Apple GCR, Commodore GCR, Amiga MFM, protected sector-gap schemes, and even weak bits. Hardware kits cost circa $30–60. The standard modern tool for serious floppy work.

• Software: github.com/keirf/greaseweazle

KryoFlux — commercial archival-grade

KryoFlux is the commercial predecessor to Greaseweazle, sold by the Software Preservation Society. Used by the Internet Archive, the Computer History Museum, and multiple national libraries. Hardware costs circa $125–150 for individuals. Produces the .raw stream format that's become the de-facto archive standard.

HxC Floppy Emulator — the drive replacement

HxC replaces a physical floppy drive with an SD card reader in vintage hardware. Instead of loading from disks, a Roland sampler or Amiga or CNC machine loads from an image file on an SD card. Invaluable for keeping production equipment running when original disks fail. Available as standalone Gotek-based firmware replacement (cheap) or dedicated HxC boards (premium).

FluxEngine — the new upstart

FluxEngine is a newer open-source project using a Cypress FX2 USB board. Similar flux-level capture; lower hardware cost than KryoFlux with a smaller ecosystem than Greaseweazle.

SAMdisk — the imaging workhorse

SAMdisk is a disk-imaging utility that handles an unusually wide range of protection schemes and exotic sector layouts. It runs on Windows and Linux and works with USB-connected floppy controllers as well as Greaseweazle/KryoFlux hardware. Essential in any floppy-preservation toolkit.

Internet Archive — the long-term home

The Internet Archive hosts tens of thousands of floppy images contributed by collectors, preservation societies, and abandonware archives. Their Disk Images and Software Library collections accept new donations. The Software Preservation Society maintains curated archival-quality images of commercial releases.

Modern uses (2026)

Floppies are still in daily production use. Here is the non-nostalgic, working-infrastructure list.

Music production — Roland samplers

Roland S-50, S-550, S-770, and W-30 samplers load their patches from floppy. Countless working producers (hip-hop especially, and ambient/drone) still use these units for their specific character. HxC and Gotek emulator replacements are now common but many purists still load from genuine disks.

Embroidery machines

Brother, Janome, Husqvarna Viking, and Bernina embroidery machines from roughly 1995–2010 accept floppy-loaded .pes, .jef, and .exp pattern files. Modern machines use USB, but a huge secondhand market and craft-community install base still runs on floppies. Ebay, Etsy, and pattern-design marketplaces sell designs on disks.

CNC manufacturing

Legacy CNC lathes and milling machines (Fanuc, Mitsubishi, Haas older models, many Japanese shop-floor units) still accept G-code programs via floppy. Machine shops keep a box of 3.5″ HD disks next to $500,000 machines because replacing the machine costs 50× more than rebuilding the load path.

Aviation (retired 2020)

Boeing 747-400 aircraft loaded their navigation database updates from 3.5″ 1.44 MB floppies until circa 2020 via the FMS (Flight Management System). The FAA Airworthiness Directive process for transitioning to newer loaders was the bottleneck. Once the 747-400 fleet retired en masse during the 2020–21 pandemic, commercial aviation largely exited the floppy era. Some older freighters may still use the method.

US military (retired 2019)

The US SACCS (Strategic Automated Command and Control System) used 8″ floppies for nuclear launch-order coordination until the Air Force formally decommissioned the last units in 2019. The replacement system uses modern SSDs. The 8″ floppy ran the apocalypse trigger longer than any other storage medium in Pentagon history.

Japanese government (banned 2024)

Japan's Digital Agency completed the removal of floppy-disk submission requirements from government procedures in June 2024. Until then, roughly 1,900 government procedures required citizens or businesses to submit data on physical floppies. Minister Taro Kono declared victory against the format after a multi-year modernization push.

Retro gaming preservation and live use

Amiga, Atari ST, Apple II, C64, and IBM PC DOS retro-gaming communities still use physical floppies for authenticity, plus flux-image archives for preservation. The DOS retro scene specifically values floppy-installed games for their era-authentic install rituals.

Chuck E. Cheese animatronics

Chuck E. Cheese's animatronic stage shows ran on floppy-loaded control data from the early 90s through the franchise's phased shutdown of the old "Rock-afire Explosion"-style shows in the late 2010s. Individual franchisees reportedly continued using the original disks even after corporate moved to digital, because replacement hardware was unavailable and the floppy system worked fine.

Retail + hardware still sold in 2026

• Wiltronix USB floppy drives — one of the few Western-market specialty resellers of USB 3.5″ floppy drives and accessories.
• Chinese OEM new-production 3.5″ drives — AliExpress, Amazon, and eBay carry USB 2.0 / USB 3.0 external drives from multiple OEMs at circa $15–40.
• Verbatim NOS HD disks — sealed 10-packs still sold on Amazon and eBay. DataLifePlus is the collector pick.
• Maxell and Sony NOS disks — production ended circa 2011, but warehouse stock continues to trickle onto the market.
• Greaseweazle kits — circa $30–60 from multiple retro-hardware resellers (Tynemouth Software, PCB manufacturers direct).
• KryoFlux — still sold direct by the Software Preservation Society (softpres.org) for institutional and serious-preservation use.
• FluxEngine — open-source; boards sold by third-party retro-hardware makers.
• Gotek + HxC / FlashFloppy firmware — the dominant floppy-emulator for retro hardware, circa $20–40 for a Gotek + SD-card enclosure.

Where to buy

The floppy market is spread across a few channels with very different price dynamics.

eBay

The primary market for vintage drives, NOS media, and preservation hardware. 8″ items are rare and pricey when they appear; 5.25″ drives are cheap and abundant; 3.5″ drives are near-free in bare-drive form. Condition claims are unreliable — ask for photos of the heads and any visible belt.

Amazon

Best for new-production USB floppy drives, NOS Verbatim/Imation sealed boxes, and some Greaseweazle third-party kits. Prices are higher than eBay but returns are easier.

Mercari JP / Yahoo Auctions JP

Japan has the deepest secondhand market for NEC PC-88/PC-98 hardware, Japanese 1.2 MB 5.25″ drives, and Roland sampler libraries on original disks. Use a forwarding service (Buyee, Neokyo, Zenmarket). Pricing is often significantly better than the US import market.

Thrift stores and estate sales

Still the best source for bulk 3.5″ disks at trivial prices (circa $0.10–0.50/disk). Goodwill, Salvation Army, and church rummage sales in college towns are productive. Estate sales of engineers, musicians, and graphic designers (circa 1990–2005) are goldmines for boxed software and NOS media.

Retro-hardware specialty shops

Tynemouth Software (UK), Retro Innovations (US), Individual Computers (Germany), and a handful of others carry preservation hardware, adapters, and freshly manufactured clone gear.

Buyer's tiers — what's junk, what's worth it

Not worth buying

• Random loose 3.5″ disks with unknown data — free if gifted, pass if priced.
• "Untested" Zip drives of any capacity — Click of Death risk; only buy tested with a known-good cartridge.
• Bulk no-name 3.5″ bulk packs — oxide shedding, low write-success rate.
• Any 5.25″ drive with visibly seized spindle or obvious belt damage unless you specifically want a restoration project.

Mid-tier — solid buys

• Sealed 10-pack Verbatim DataLifePlus HD — circa $10–25 per sealed pack. The gold-standard write-capable media.
• Working 3.5″ USB drive, new-production — circa $15–40. Baseline tool for any modern floppy work.
• Greaseweazle kit — circa $30–60. Upgrade path into serious preservation.
• Clean Commodore 1541 or Apple Disk II with controller card — circa $80–200. Functional plus historical.
• Boxed commercial software with original disks + manual + codewheel — specific games (Ultima, Monkey Island, LucasArts titles) hold value indefinitely.

Top-tier — the grail items

• Original Shugart SA800 8″ drive, working — rare, museum-grade, circa $200–600+ depending on condition.
• Apple Disk II in original box with controller card — circa $250–800 boxed, documents provenance of early home computing.
• Unopened boxes of 8″ floppies — sealed NOS is vanishingly rare, circa $80–200 for sealed originals.
• Sealed Hi-Capacity media: Zip 750, Jaz 2 GB, LS-120 SuperDisk NOS packs — uncommon and expensive relative to capacity.
• Roland S-series original sampler library disks — still sought after by working producers.
• KryoFlux — not cheap, but archival-grade output and institutional provenance.

Glossary

MFM (Modified Frequency Modulation)

The dominant floppy encoding from 1978 onward. Packs data at 250 kbps (DD) or 500 kbps (HD). Used by IBM PC, Amiga, Atari ST, and Apple SuperDrive.

GCR (Group Coded Recording)

Apple II and Mac (pre-SuperDrive) encoding. Groups of data bits are mapped to longer "nibble" patterns that guarantee enough flux transitions for reliable clock recovery. Incompatible with MFM controllers at the hardware level.

Index hole

Small punched hole in 5.25″ and 8″ disks that the drive uses to locate track start. Single-sided disks have one; some protection schemes used the absence of the index hole in unusual positions as part of the protection.

Write-protect notch / tab

Physical mechanism that disables writes. 5.25″ disks are protected when the notch is covered; 3.5″ disks are protected when the sliding tab is open. The convention flipped between generations.

Flippy disk

A single-sided 5.25″ disk with a second notch cut into the opposite edge so the user can flip it over and use both sides. Saved money in the Apple II / C64 era.

Head alignment / azimuth

The physical angle of the drive head relative to the tracks. Drives drift over time; misalignment causes intermittent reads. Professional alignment requires a reference tape and is increasingly hard to get done.

SS / DS / DD / HD / ED

Single-Sided / Double-Sided / Double-Density / High-Density / Extended-Density. Capacity and coating designations. Higher-density media requires a higher coercivity magnetic coating; a DD disk formatted as HD is unreliable.

Track 0

The outermost track; home position for the drive head. Most controllers detect Track 0 with a microswitch or optical sensor. "Track 0 error" is a common drive-failure symptom.

Bad sector

A sector that fails to read reliably. FAT12 marks bad sectors in the FAT; copy protection intentionally created bad sectors and checked that a legitimate disk still had them (a pirated copy often silently "repaired" them).

Sector interleave

The order in which logical sectors are physically laid out on a track. Apple DOS 3.3 used a 2:1 interleave (alternating sectors) to give the CPU time to process each sector before the next one arrived under the head. ProDOS used 1:1 because the 65C02 was fast enough.

RPM (300 / 360)

Spindle rotation speed. 5.25″ drives spin at 300 RPM except the IBM PC/AT 1.2 MB HD drive, which spins at 360 RPM. 3.5″ drives always spin at 300 RPM. Mixing speeds caused endless compatibility headaches.

Tunneling erase

A drive-head design where a separate erase head creates a clean "tunnel" in the magnetic coating just ahead of the write head, preventing adjacent-track interference. Standard on quality HD drives.

Write precompensation

Circuit that shifts the timing of write pulses on inner tracks to compensate for the physics of higher linear density near the center of the disk. Set via drive jumpers or BIOS on older PCs.

Nibble / flux

A "nibble" is 4 bits, but in floppy preservation it usually means a raw encoded byte from the disk (what Apple II copiers operated on). "Flux" is the even-lower-level stream of magnetic transitions — what KryoFlux and Greaseweazle capture.

Click of Death

Iomega Zip-drive failure mode where the head crashed into the cartridge repeatedly, damaging both. Contagious across drives via shared disks.