dbacl is a general purpose digramic Bayesian text classifier. It can learn text documents you provide, and then compare new input with the learned categories. It can be used for spam filtering, or within your own shell scripts. Sometimes it plays che
SpamList is a simple system to maintain your internal whitelists and blacklists for spam control. Includes PHP scripts to manage the master list and shell scripts to distribute to one or more servers.
phpMyBlacklist: A project for creating and managing an email blacklist or RBL lists. The project includes steps for setting up the required zone in your name server, the required database, the web administration and a simple shell cronjob script.
Tarbaby is a new threshold and rate limiting spam prevention tool. The intent is in creating a thresholding and verification engine to be tied into other spam prevention tools.