An iptables script that protects against stealth scans, port scans, OS fingerprints, and other types of scan
SlackFire is an iptables script written especially for Slackware, my favourite Linux distribution in this corner of the Galaxy.
FireHOL is a stateful iptables packet filtering firewall configurator.
Easy Firewall Generator is a Web application that generates an iptables firewall script.
IPv6 FireWall script is a firewall based on ip6tables.
PacketFlow Firewall Generator is an XML based firewall generator.
EtherDam is a firewall configuration engine that relies on iptables.
Uruk is an iptables firewall script that is useful if you need similar packet filtering configurations.