Here's another I didn't see posted here.
Avast! Antivirus Home Edition(free), fully functional with 6 resident scanners. I've been using it for years and prefer it over AVG.
FREE avast! antivirus 4.x Home Edition, anti-spyware & anti-rootkit for Windows You do have to renew your license every 14 months but its still free.
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Core2Quad Q6600@2.4ghz
4096mb DDR2 Kingston Dual Channel PC6400
Zotac Geforce GTX460 768mb
Windows 7 Premium 64bit
Asus P5N-E SLI
3.25TB total mixed volumes
Auzentech X-Raider 7.1
NZXT Lexa Blackline Gaming Case
Antec Trupower Quattro 850w