I’ve been using Panda Security’s free Cloud Antivirus for awhile and I must say I’m impressed. It’s there, but you’ll never know it unless you look (the little panda icon in the system tray). I rarely get malware of any kind, but Cloud AV has caught a couple of things that were probably drive-bys. It’s so transparent that I actually had to go check on it before I noticed that malware had been caught.
This is a perfect set-it-and-forget-it AV for the regular user. It’s free, self-updating and doesn’t require any decisions on the part of the user. But the great part about it is how it works. Watch the video. It’s really slick, blocking malware within 6 minutes when encountered by anyone who has it installed; it’s truly real time updating.
That’s my two cents. You be the judge and try it for yourself.