What is the lightest weight free firewall software?

Cabalo-

What do you think of-

http://www.matousec.com/

I've been onto them for a few years now...

I just use Windows too.... do you think I should upgrade to an acutuall app?

comodo is free and really strong

Comodo is pretty resource intensive sometimes though. On some systems it bogs down quite a bit. Both myself, my roommate, and one of his friends have tried it on Win7x32 and had issues.

Avast seems to work pretty well from what I've seen, though. Still, not the most enjoyable program to use.