If you are talking strictly about spyware blockers that run in memory and are active in intercepting spyware, two that I know of and use are Pest Patrol and Spy Sweeper. Pest Patrol is a yearly subscription. Spy Sweeper is free with one free definition update, then it is a yearly subscription. Both of these will sweep the hard drive for programs, cookies and registry entries that look suspicious in addition to interception. Ad Aware, the free version, does not run in memory. However, it will run through the hard drive as the other two do to alert you to what may be spyware on your hard drive. Of the three Pest Patrol seems to be the most comprehensive.

What I suggest is running ad-aware and spybot regularly (once a week) and then to prevent spyware active x controls you can use spyware blaster. It'll stop spyware from invading ie, and it doesn't use system resources (other than a little hard drive space).

A good firewall program can tell you if programs are sending/receiving data and allow you to block them as well. A lot of people swear against i but I have been happ with zone alarm pro.

Quote:A good firewall program can tell you if programs are sending/receiving data and allow you to block them as well.

Good point. I used to have Zone Alarm block the adware parts of imesh so I could use it without being spied on.