I gotta tell ya, I really like Avast's Web Guard. Without being nasty about another free AV, I will just comment that unlike that one, the Avast Web Guard has stopped a a few trojans for me "before" they got into my PC. Now that's protection. Also there is some spyware protection in the free version that is not offered by the other free AV's. Avast is the first free AV that actually made me want to pay for a Pro version. No other AV or other security program has ever convinced me to do that, and because I am one of those freeware kind of people, I think this speaks volumes as to how good Avast is.