Can BitTorrent kill your drive? I don’t know, but Ed at Quality Peoples seems to think so. After what he calls “Heavy BitTorrnt use” he had 2 drives go bad on him. I personally haven’t had any problems (yet), but it’s something to consider when your downloading that pirated copy of Battlestar Galactica.
I’ve definitely experienced this a few times with Bittorrent. But only when I use the startup drive as the save area. Since then, I’ve switched to Azureus, have had the application save to my second harddrive and haven’t had any problems at all.