OPNwall wireless desktop & wallmountable m0n0wall appliance is a complete embedded fan-less firewall appliance that consumes less than 5Watt, it provides many of the features of commercial firewalls at a fraction of the cost.
m0n0wall is based on a bare-bone version of FreeBSD, along with a web server, PHP and a few other utilities. The entire system configuration is stored in one single XML text file.

The OPNwall desktop edition is a true out-off-the-box firewall experience it is very easy to configure with a clear Web interface.

just a few minutes and you are up and running, in fact the aplliances boots in less than half a minute.