Best FREE Anti-Viral Setup?

On my oldest boxes, I'd been running AVG, Spybot, Ad-Aware, Zone Alarm as my active products.

On the newer boxes, I've tended to stick with AVG and Spybot, but also added Defender (something I plan on removing, as I don't like it), Spyware Blaster, Spyware Guard, and Zone Alarm.

I've recently had people tell me that just Avira and Comodo will take care of most anything, if you surf smart.

You guys, however, use (from what I've seen) MBAM, ComboFix, RSIT, HJT and a couple others. But those all seem for targeted fixes and log reading.

What's a solid, always-on setup for anti-virals... that's free?

 

In my defense, I'm asking more about a comprehensive setup for prevention and not just a single product, like he was for an anti-virus.

Then again, I split so many hares on a daily basis, they're starting to multiply like rabbits. ( Get it? >_< )