Free Corporate Spyware protection: Shavlik NetChk Spyware
Shavlik has recently started to offer NetChk Spyware for free on their website (50 seats max). NtChk Spyware is one of the best and most powerful anti-spyware solution currently available for SMBs. It is fully automated and will keep your network safe from the nastiest and most current adware, spyware, malware and nonbizware. If your environment is infested by these kind of nasties, I would definitely recommend that you give it a try.
Shavlik are also the makers of HfNetChkPro, my favorite patch management solution. If you are in need of something that is better and more powerful then WSUS to deploy your Microsoft product updates, you can have a look at the review we did of the product right here.