The only "good" free one I used to have was Spybot - Search & Destroy (I liked it 'cuz of Metallica). The one that I found that wasn't so much of a resource hog is PC-cillin by TrendMicro. Real time antivirus/spyware stuff that would block you from even opening a suspected page and tell you why. Plus, it was pretty inexpensive - I paid like $40
and that's good for up to 3 computers.
Now...where's my TrendMicro affiliate code...
