Ok, I've got pretty much the same question as JJ did... Except I'm actually looking for anything BUT a Windows based solution. In-my-not-so-humble-opinion, Windows personal firewalls are all crap... Mostly because Windows is crap.
Anyway, I'm looking for an opensource or freeware firewall that is:
1.) Easy to use! And I mean really easy to use!!! My folks have a harder enough time turning their computer on and getting on the web! I need something even a great grandparent could use!
2.) Can be run on a PC with as little as a Pentium 120MHz w/16MB RAM.
3.) Has a host of remote management options (i.e. https, VNC, SSH, and/or X-server.)
4.) Can 'instantly' notify a user of 'un-authorized' net access in much the same way Windows based personal firewalls do.
The first three are essential. The fourth I'm not sure is possible, given that you probably need to hook into the client OS... But who knows, I've only recently started this odyssey. Any guidance would be welcome.
BTW, I should probably mention that I already have a 'hardware' firewall in the guise of a Linksys WRT54G router. Unfortunately the "ease of use" requirement disqualifies it. While I'm computer literate enough to use it, I know my folks are not. The last thing I want to do right now is be solely responsible for maintaining it or any other router, gateway, bridge, or firewall.