If you are using Firefox, you can get a complete BitTorrent client from within you browser using the AllPeers browser extension. AllPeers makes it so you can download and share torrents from within your browser. If you've ever wanted to share torrent files with your friends and family, this is the perfect tool for the job. It's faster than most BitTorrent clients, it offers full encryption (take that Comcast!), and since it works in you browser it works on any type of machine that Firefox works on (PC, Mac, Unix, etc). If you are looking for a free BitTorrent client, this is a good place to start.