Today’s featured promo on MacUpdate offers SpamSweep for US$12.95 (48% off, retail $25). “SpamSweep is an advanced bayesian spam filter with a simple, easy to understand interface. SpamSweep seamlessly combines many filtering technologies, including domain and relay blacklists, sender whitelisting, and a bayesian filter to automatically delete spam messages before they’re downloaded by your email client.” SpamSweep requires Mac OS X 10.3 or later.