a good firewall

Hay /comp/,

What's your favorite firewall program?
I have zonealarm and IMO it is not so great.
After tweaking it to allow minimal traffic to/from my computer, it ran fine for months until all of a sudden it started giving me Generic Host Process Blocked messages from various DNS caches from my ISP. 

What's with the Unix elitism on here? I know it feels really cool to set up an OS just to firewall, but a) that's a total waste of time, b) not everyone has a spare computer, and c) a 15 dollar router with a software firewall is a lot more practical than running an entirely different computer 24/7 tacking onto your electric bill just because it's cool. You don't need security like that... Unix users, kings of inpracticality.