NoCatAuth is the CaptivePortal that is being developed by NoCat (primarily SchuylerErle, with widespread contributions). It does support having an open system with configurable restrictions to bandwidth and ports based on if the user is a trusted member or not. --AndrewWoods (edited ancient text by MichaelCodanti)
There was a some SlashDot coverage as well. Way to go guys! -- AdamShand
A successor written in C is in the works, suitable for embedded-style applications:
See also: NoCat, NoCatAuthWishList, NoCatAuthTesting, NodeSplashPages, NoCatAuthWorkFlow