Case in point: for the past few months I've had the side cover of my computer off, for heat reasons, esp. since the CPU fan keeps crapping out every week. Anyway, alongside this opening, I have another computer, and the keyboard for that computer rests on top of the case.
Apparently, the power cable to my HDD had a slight short in certain positions, so that whenever the cable was moved or touched, the power on the drive would cut out and in, stopping and starting the drive's spin suddenly. This would happen more or less every time I picked up the 2nd computer's keyboard to type something, as its cable passed right by the HDD power cable.
But I didn't know about the power cable problem at the time, and thought that the HDD (IBM, 17Gb) was crapping out. I'd hear it restarting itself a bunch, clicking and clacking to get the heads into place or whatever. But in-between these times of clicking, the drive would behave completely normally. So I started taking data off of it, to prepare for the worst.
Then I finally realized somehow why it was suddenly dying, and closed the computer panel up. I haven't had problems since then.
But the point is this: that drive had its power cut off suddenly dozens of times, sometimes even in the middle of disk writes and the like. And after all that, withthe source of the problem solved, it works perfectly.
Sandwich likes IBM. 