I'm pleased to announce that a captive porta for wifi networks I wrote
with mod_perl has been open sourced.

Here it is on CPAN:

http://search.cpan.org/dist/App-SilverSplash/

And the blog announcement:

http://blog.silverliningnetworks.com/2010/08/announcing-the-silversplash-open-source-captive-portal.html

Most other captive portals use C and posix threads, so Apache and
mod_perl has given some great stability for this application as
opposed to what else is out there.