IPCop is really a great project. In brief: it's a rock-solid open source (which is good for security) firewall, easy to administer, it has low hardware requirements and it's functions are expandable thanks to all the addons available. If you need more informations, please visit it's web site.

After using it for several years, I'm going to give my 2 cents. Here you can find the outcome of my own work on the subject.

In this section I've collected some patches to IPCop and/or its addons. They are the result of simple needs, but maybe someone else could find them useful, so I'm sharing.

Patch	Description	Version
Disk I/O	Kernel patch to publish disk performance data via snmp	1.4.21
	Kernel patch to publish disk performance data via snmp	1.4.18
DHCPd static	Enables name resolution for DHCP static leases	1.4.18-21
Ovpn CCD	Adds client-config-dir directive to Zerina	1.0.0