if you dont want to pay, either use Avira or my personal fav, Avast.
if you do want to pay i can recommend BullGuard, which is a complete security suite, including firewall and whatnot. it doesnt eat much, runs nice, updates itself a couple times a day and comes with a 1GB online drive for crucial backups (atleast the gamers edition did). the great deal on bullguard gamers edition is, that, if youre a gamer, you dont need to bother with allowing your games through the firewall, as it automatically keeps track of your games.
As i said before, Avira seems to be doing well. It updates throughout the day and i get about half a dozen notifications a day. Though, again, i profess that i perhaps do not know if these are just 'feel-good' 'false-positives' but i haven't had any issues thus far. Also, i will admit that i haven't delved into it as thoroughly as i'd be most comfy with due to schedule, time and life constraints. Excuses, i know. =/
Point is, for free, it seems to be lovely thus far. i'd like to investigate some higher end options, like the gamer's options in Bullguard that Mendoza recommended. Though i really only play one game online and not that often anymore, so i wonder if it is worth spending the $ on. i never had problems whilst playing before after all.
That's where i stand now.
Why not keep each all each other informed and going by keeping this thread open, consistent, constant and updated?
Just and idea.....