What do you use to keep your PC secure, other than Anti-Virus software?

Thank you for your suggestion. I had never heard of Vipre Antivirus + Antispyware before. I will look them up.

My windows 7:
MSE + sandboxie (paid verison)
i run browser and new software sandboxed so no malware can come from the internet

I use noscript with firefox and malwarebytes along with my standard avast antivirus. Pretty hard to get a virus with those set up and some common sense.

The computer security is a very important topic in my opinion. I use AVG antivirus, Lavasoft personal firewall, and of course Mil Shield against all computer privacy breakers.