Michael Tsai has released SpamSieve 2.5 [1], the latest version of his popular spam-filtering tool for Apple Mail, Emailer, Entourage v.X and later, Eudora 5.2 and later in Sponsored or Paid mode, GyazMail, Mailsmith, Outlook Express 5, and PowerMail. Among numerous enhancements [2] in SpamSieve 2.5 are improved accuracy for the image spam that had started to slip through, greater performance and smaller memory usage, and a new software update feature for simplifying updates. SpamSieve 2.5 is a free update for registered users; new copies cost $30. A 30-day trial version is available as a 3.6 MB download.
[1]: http://c-command.com/spamsieve/
[2]: http://c-command.com/blog/2006/10/30/spamsieve-25/