Quinn Norton has a terrific article in today's Guardian on the tension between infringing and noninfringing uses for BitTorrent:
Anyone can put up a link to a small ".torrent" file on their website, host an initial "seed" file, and set up an independent "tracker" that points downloaders to each other. If the file becomes popular, copies begin to sprout up around the internet, at no extra cost.
This, while unpopular with the MPAA, was great for Shane Felux, maker of the fan movie Star Wars: Revelations. Felux and his wife, Dawn Cowings, worked with fans all over the world for three years to make a surprisingly beautiful 47-minute movie, complete with Star Wars-quality special effects. Revelations has moved thousands of gigabytes a day of 250MB movies and a DVD version. George Lucas is fine with fan creations as long as they don't slander his original and are free. Since Felux and Cowings can't charge, paying for hosting wasn't an option. BitTorrent allowed that burden to be carried by fans downloading and sharing the files themselves.
(via Ambiguous)