Hoaxes, Rumors and Urban Legends
Hoaxbusters: A project of the US Dept. of Energy, this searchable index allows you to identify e-mail hoaxes.
Snopes's Urban Legends Reference Pages: A great resource, where investigations on each rumor are performed by Snope staff, who fill in background on the hoax/rumor and, where possible, supply citations to back up their reports.
Truth or Fiction: A resource for checking internet-spread rumors and hoaxes.
Urban Legends and Folklore: Information on all kinds of rumours and hoaxes, both on and off the Internet.