Hopefully everybody knows about NUnit, NAnt, and FitNesse, but here are some other cool tools/websites.
Time Snapper - Track your time by taking screenshots through out the day to see what you're working on when.
SideStep.com - Check all travel sites for the lowest rates
Digg - News for the people, by the people. Users decide the most popular stories.
http://del.icio.us/ - Post your Favorites online and see how many other people are saving the same link