Thanks to Underclocked . . .

[RandyWakeman]

http://www.grisoft.com/us/us_dwnl_free.php is a free anti-virus program that has worked superbly, and puts very little drain on your system compared to others.

It was the great and powerful Underclocked that turned me on to this little gem of a freebie. If you aren't protecting your system by other means, or if what you are currently using really puts the brakes on your system-- you might want to give it a test drive.

[Underclocked]

Glad you like it.  "great and powerful" must be a nice way of saying fat and ugly.  

Some worthy contenders that are also free in the anti-virus realm are:

 http://www.avast.com/i_idt_153.html  Avast seems to work quite well but uses more memory than AVG.

MS and CA team up to offer eTrust for one year free.  This one includes more than just an AV if you so choose during the install -
http://www.my-etrust.com/microsoft/index.cfm?&CFID=1921302&CFTOKEN=1f15fea119ee2e4a-BA97099C-0282-BEFC-D129E91ABA54E2EE

I have the eTrust on my wife's pc.  Seems to be doing the job.  Didn't install the extras.

If you were ever the proud owner of a retail copy of McAfee version 3 or 4, you can get a free "perpetual" version of McAfee AV at http://software.mcafee.com/lcas/

While we're protecting our computers - you might want to get Ad-Aware free version from http://www.lavasoft.de/software/adaware/  .  Download, install, update and then check for problems.  Likewise, Spybot - Search & Destroy from http://download.com.com/3000-8022-10122137.html can help rid your system of spyware/adware and maybe make life online a bit less hectic.  Both programs should be updated and ran periodically to keep things healthy.

And, finally, the Google Toolbar (search for it a Google.com) is a pretty effective and free pop-up blocker.