Since its inauspicious public appearance 10 years ago bittorrent has become one of the major download formats. With good reason too: it's fast, equitable and efficient. If you haven't yet installed a Bittorrent client on your PC, you should as there are some great freeware clients available. In Bittorrent the best clients are free. (In fact, if a client costs money, it is most likely a scam).
If you are unaware of the bittorrent protocol, you may take a look at my article, What is Bittorrent, as well as the listings within Searching for Torrents and Finding Legal (and free) Torrents to see the massive amount of content available through bittorrent.