I wish torrents didn't have such a bad reputation for piracy. It really is an awesome way to download all sorts of things. On that note, Gabe was entirely right when he said piracy is a service problem, not a price problem (or something like that). Most people that I know that pirate, do it because it is just the most convenient and straight forward (No BS/DRM). If the big media corporations would fully embrace the Internet and adjust their business models accordingly, I think piracy would greatly reduce. (Obviously there will always be the minority that will pirate no matter what)
Notable examples of BitTorrent being used legally are Blizzard using the BitTorrent protocol to distribute game clients like Starcraft, WoW, Diablo, etc. and of course Linux distros. I know there's plenty more but I think that gets my point across.