I've had certain government agencies as clients, and they wanted some hard drives replaced under warranty, and I had to explain to them that if they wanted the drives replaced under warranty, the drives had to be shipped back to the manufacturer.
The way they "wiped" the drives was putting them through a metal shredder! It's hard to recover data from 1/2" square shards of metal!
Mark
I guess they preferred replacement rather than repair, eh? ;)