Spamprobe is a fast, intelligent, automatic spam detector using
Bayesian analysis of terms contained in emails. Works with procmail,
maildrop or a similar tool to produce a complete server or client side
spam filtering system.

Features:
 * Spam detection using Bayesian analysis of terms contained in each
   email.
 * Automatically learns from incoming mails as they are
   classified. Incorporates user's feedback to tailor classification to
   each user's personal tastes.
 * Analyzes image attachments to derive useful information from them.
 * Natively supports mbox, MBX, and Maildir mail box formats.
 * And many more..