I would like to add another option. Smoothwall is a hardened Linux based firewall and includes IPSec, Snort , IPchains , forwarding etc AND it runs on older machines. The system is designed to be the sole resident and has a nice web interface. I have it running on a P100 with 32 Mbytes of RAM with no problems and I believe it is very secure. It is also very easy to set up and supports DMZ zone. You can download it from
http://www.smoothwall.org and I highly recommend a donation if you find it useful to keep the project going.
I run a couple of different servers (AOLserver,Postgresql etc) on different machines and seems to work fine. We also replaced Gauntlet at work with Smoothwall and good luck there.
cheers
Jamie
