I've seen a whole batch of hard drives fail: one-by-one the company's employees' PCs failed over a period of a week or two. They had all been bought together in

I've seen a whole batch of hard drives fail: one-by-one the company's employees' PCs failed over a period of a week or two. They had all been bought together in a single upgrade. I (on a Mac) was unaffected (and no doubt a little smug).