Comment spam prevention for blogs.
http://akismet.com
Widgets · Comment System
Get access to data on 1,224,259 websites that are Akismet Customers. We know of 236,354 live websites using Akismet and an additional 987,905 sites that used Akismet historically and 142,844 websites in the United States.
Get a list of 1,224,259 websites using Akismet which includes location information, hosting data, contact details, 236,354 currently live websites and an additional 91,039 domains that redirect to sites in this list. 987,905 sites that used this technology previously and 142,844 websites in the United States currently using Akismet.