I've just got an old Watchguard FireboxII up & working, yep even sourced the software for it.
Only one problem, how does one set up port forwarding on it for either
A) virtual open access (on just the one specific port to _any_ remote IP listening/connection) &/or B) To a specific server (not very important but there have already been screams about MSN not working fully as video is down)
Watchguard aren't very forthcoming unless you are fully registered (of course I'm not) & what documentation I can find appears (at my level of understanding) a little obtuse.....
The reasoning I have for running the Firebox is that the more modern FVS114 has locked up on a few occasions so I was trying to find something which wouldn't be swamped by traffic & just be generally more stable.
A worse choice scenario would be setting up a specific machine in a DMZ but I'm loath to do that & so, at the present moment, I have not looked for any guidance on that issue.