Computer Related
F-Secure -
http://www.f-secure.com/virus-info/hoax/
HoaxBusters -
http://hoaxbusters.ciac.org/
McAfee -
http://vil.mcafee.com/hoax.asp
Network Associates -
http://vil.nai.com/vil/hoaxes.asp
Sophos -
http://www.sophos.com/virusinfo/hoaxes/
Snopes -
http://www.snopes.com
Symantec -
http://www.symantec.com/avcenter/hoax.html
VMyths -
http://www.vmyths.com/index.cfm
Health Related