http://www.wilderssecurity.net/spywareguard.html - missed an "S" out there!
Not used it myself, but heard reasonable reports - it doubles up on, but is reckoned to be better than the "teatimer" feature in Spybot S&D, so if using with Spybot S&D, you'd probably want to turn that feature off unless paranoid (it works in a slightly different way, but with a similar catchment)