From LedHed's Wiki
References:
http://www.howtoforge.com/linux_iptables_sarge Start Here
http://iptables-tutorial.frozentux.net/iptables-tutorial.html Some Technical reading for those nights when you've run out of Ambien
http://www.netfilter.org/documentation/index.html More Technical reading (You really don't want to read all of this, just wing it!)