The SwarmPlayer v1 was a Python based Bittorrent/Internet TV viewer. It allowed you to watch BitTorrent-hosted videos on demand and plays live Tribler streams. It is based on the same core as the Tribler TV application. More on the SwarmPlayer can be found at the pages about our large-scale trial we did in July 2008.
The SwarmPlayer has been superseded by the SwarmPlugin. You can still build it yourself (http://svn.tribler.org/abc/branches/mainbranch/Tribler/Player/Build).
In September 2010, we released SwarmPlayer v2 which is a browser plugin that adds P2P video streaming protocols to you browser under the tribe:// URL scheme. This allows direct P2P streaming of video into the new HTML5 <video> and <audio> elements. It was tested in a large-scale trial with Wikipedia, read more about it at http://swarmplayer.p2p-next.org/