Read this post about a new service called Dijjer. It’s a Bittorrent-like distributed downloading service which allows files to be distributed to multiple clients without sucking away all your bandwidth.
The main difference to me seems to be the ease-of-use factor -> to share a file using dijjer, simply add a “http://www.dijjer.org/get/” to the front of the actual file URL. So, to share “http://www.karipuf-file.com/karipuf-file.zip” (this is a fictitious URL, please don’t try to get!) the dijjer-enabled” link is: “http://www.dijjer.org/get/http://www.karipuf-file.com/karipuf-file.zip”. There are apparently other benefits, for e.g.Chris Holland in the above link also mentions that Dijjer also allows uploads from behind a NAT though this has not been a problem with me in the past (have been bittorrenting from behind a NAT and was apparently still able to upload..).
While you’re in the mood, check out the Million Book Project (a bit unrelated but what the hey :-))