my favorite fails for the last 15 years is:
Ati drivers, in the era of the Rage 128 - I recall a time when It's hard to make working an ATI All-in-wonder 128 without it's original drivers from the installation cd. Each news drivers where a nightmare to remove and to bring back the card stable.
RDRAM : when I worked into a computer shop, when this sort of ram has appear, it's was write in the sky - Beware of this scam! We have sell some systems with RDRAM but the sdram remain very popular until the DDR appear on the market.
Pentium IV Prescott in it's first incarnation - Somewhat underperforming cpu for it's TDP and a very long 32 stage pipeline... So, I could say these cpu's was enough stable to be usable and enjoyable has a heater to replace my old Ciryx
Windows 95 version A with is 15 floppy of doom and basic pnp- because the second was better than 3.1 and the third one is even better.
Next cpu's and board was the ancestor of the AMD K6 but was very hard to get fast to run under Windows 95
Cyrix PRxxx series processor because these have virtualy no FPU vs Pentium cpu of the same time. But, I had one for two week in my pc and I loved the way it heated my house basement
IBM MCA proprietary bus - too proprietary to worth to buy but very interresting architecture for it's time vs the ISA and VLB
LS-120 is not famous as the Zip drive, but do you remerber the Syquest Ez drive?