Roaring Penguin Software Inc. publishes for DNS-based lists for Hosted CanIt customers. These lists are automatically entered into the Master RBL list (but no rules are created automatically.)
The lists are:
These are machines known to have trouble getting past greylisting. The machines are very likely compromised PCs. We recommend making a rule to add one point for machines on this list, and also to extend the greylist period (if you use greylisting) to 60 minutes.
These are machines known to send mail to many nonexistent addresses. We recommend a rule to add one point for machines on this list.
These are machines known to send spam and relatively little non-spam. We recommend adding three points for machines on this list.
These are machines that send relatively little spam, quite a lot of non-spam, and have no trouble with greylisting or sending to nonexistent recipients. We recommend subtracting 0.5 points for machines on this list.
These are machines that are on the edge of being considered good or bad.