BitTorrent Mainline: the original Torrent client (Windows, Mac, Linux...)
Azureus: a very feature-rich client in Java (Windows, Mac, Linux...)
µTorrent: a fast, smaller-footprint client (Windows)
BitTornado: TheShad0w's extended version of Mainline 3.x (Windows, Mac, Linux...)
ABC: another fork of BitTornado (Windows, Linux)
Brian's BitTorrent FAQ and Guide: everything you need to know about BitTorrent. Required reading for all new users
PortForward.com: help on setting up port forwarding on your router or firewall.
Aerial Telly: A television review site which concentrates on British television but which also covers some American shows and features general comment on TV and media
OffTheTelly: Great reviews of television, interviews and tv related articles.
TheCustard.tv: The television guide for switched-on people. 'Coming Up' section, tipsheets, highlights, and some very funny and cutting reviews.