Its been a week since I am playing around pfSense – a firewall solution based on m0n0wall (which, in turn, is based on FreeBSD and lots of open-source tools). For the time being it seems to work fine and handle the small LAN (around 40 users + 7 servers) with no problems.
The cool stuff around it is that it has WebGUI for all its configurations which makes it to be a nice replacement for those 3com ADSL routers people are usually using in such places.