Well, I found a big empty space in the HOWTO's out there lacking in information about the iptables and Netfilter functions in the new Linux 2.4.x kernels. Among other things, I'm going to try to answer questions that some might have about the new possibilities like state matching. Most of this will be illustrated with an example rc.firewall.txt file that you can use in your /etc/rc.d/ scripts. Yes, this file was originally based upon the masquerading HOWTO for those of you who recognize it.
Also, there's a small script that I wrote just in case you screw up as much as I did during the configuration available as rc.flush-iptables.txt.