There is an article on Security Focus talking about ICF:
ICF is an excellent security tool for most people. It blocks most attacks from the Internet. And it works automagically with applications that are aware of the ICF API. It has support for industry standard protocols like FTP, H.323, and PPTP. However, if you are a corporate user and/or a power user, you’ll probably want another personal firewall that allows more granular control. [security focus]