Deluge the bit torrent download application is great and very usable. I have used it in other ubuntu versions when it was bundled with it. I really love this application and I believe that it downloads faster then most of the other bit torrent applications.
I just installed this one to see how it looks. (Screen shots coming tomorrow as it is 8 pm here)
Deluge is licensed under the GPL version 3 and I license my software under the GPL version 3 also.
This program is available for Windows, Macintosh, BSD and Linux. You can get it from http://deluge-torrent.org to download. For a debian package that is not in the Ubuntu repos you can get it at http://www.getdeb.net/download/3300/0 That is for the Ubuntu 8.10 release that is coming out tomorrow.