Got spam? Apple's Mail does a really great job of keeping my mailboxes spam free, but every now and then a few messages slip in. If you're ready to bring out the big guns, check out Bains Software's SpamSweep, which is a bayesian spam filtering system. SpamSweep makes use of domain and relay blacklists, sender whitelisting, and a bayesian filter to automatically delete spam messages before they're downloaded by an email client. Check it out if you're seriously anti-spam. SpamSweep is priced at US$20 and requires Mac OS X 10.3 or later.