"IMHO, antiviruses is worser than viruses - they sit in your system and eat your memory/cpu resources and in 90% of cases unable to do anything when new virus intruding into your system. Living with antivirus each day is more pain than being infected with virus once in year."
This is true of most antivirus software. I've been using AVG for antivirus on Windows, and it's nicer. On my machine it takes up about 2.3 MB of memory. I'm using the free version. I don't believe it prevents infection like other antivirus software does (though it may scan e-mail--I don't use this feature). This cuts down on the CPU usage, because it's not monitoring my files all the time. It has a scanner that you can run over your hard drive(s), which you can schedule, and it downloads updates automatically. That's it. Every few months it gives me a pop up saying it's "about to expire", and they try to get me to buy the commercial version, but when it does expire I can just download a new, updated free version.
---Mark mmille10@comcast.net