I work on a lot of computers for friends and family that tend to need various means of repair work. Sometimes those machines are badly damaged and not worth repairing because the cost of the parts outweighs the cost of a new machine. In those cases, I often part out the machines to harvest whatever is salvageable. Sometimes they get used to make zombie machines out of all the random pieces, but more often than not I am able to use the parts to fix other people's broken machines. In the end, I sometimes end up with a bunch of random hard drives laying around that are perfectly good and some are even of a decent size.