http://www.brighttiger.com/products/default.htm
http://www.resonate.com/products/index.html
http://www.checkpoint.com/products/floodgate-1/index.html
http://www.ntguard.com/gpfeatures.html
http://www.webspective.com/
For more information about this list, including removal,
see this url: http://www.iea-software.com/maillist.html