GNU Firewalling tools. Formerly known on Freshmeat as ipchains-firewall.
The Plague provides a web UI to a MySQL db of parsed syslog data. The focus has been security reporting. The logs supported (so far) are NetScreen firewalls, Cisco routers and switches and PIXen, Gauntlet firewalls.
chainssh is a shell script to smplify the ssh login via multiple sshgateways/firewallgateaways. e.g. connect from homehost via sshgateway to a clusternode with one command.