I used to use ESET, but it has so many false positives and it's so freakin' expensive. If you live in the US, Amazon usually sales a single license of Kaspersky's Internet Security for about $10 a year around Christmas, or 3 licenses for $20. I love the added firewall and it doesn't think 'everything' is a virus. But I'm cheap. I definitely got tired of paying $40 a year for antivirus protection that seems worse than what I'm using now.