The Composite Blocking List
Junk Email Filter uses innovative techniques to fight spam. They have been the leader in introducing several new spam fighting technologies. The system also sends out automated notices to alert spam sources of problems and to get feedback in case they have a problem rejecting good email so that they can fix problems that they don’t know about. This helps ISPs and office network admins find and shut down virus infected computer reducing spam across the planet. Their view is that the best way to fight spam is to stop it at the source.
This list is not an angry list. They focus on the reality of what really works. Their position is that if you are a spammer they want to block you. If you are not a spammer they want to make sure your email gets delivered.