-Alexa the Web Information Company
--http://www.alexaholic.com/
-URL Investigator
--http://www.urlinvestigator.com/
-socialmeter
--http://www.socialmeter.com/
-aguse.net
--http://www.aguse.net/
-Statbrain.com - Tells you how many visitors any site really has
--http://www.statbrain.com/