I use to use norton antivirus 2002-2005, but it was a resoure hog. I like avg, but it found 2 trojan horses and didn't delete them (norton use to do that, before I got NAV 2005) and it was a pain to actually track those files down through AVG to manually delete them.
Some people claim NOD32 is the absolute best antivirus software out there. what are your opinions?