I suspect most people's use of the torrent protocol comes in the form of a separate p2p software client (e.g. Azureus or Transmission), indeed, this is the method I have been looking at for my research. I was always award, however, that more methods existed.  I was very impressed with BitLet - a java applet that was based in a web-browser that allows you to torrent-away.  But more methods of browser-use have also since emerged...

- Machsend; a non-Java based sharing client that uses Ruby and Yahoo's Browserplus extension.
- Littleshoot; a powerful sounding plugin for most browsers with integrated download and search.
- and now BitLet are looking to stream video using p2p too!