WiCap is a Perl based CaptivePortal solution written by BrianCaswell for NovaWireless. You can find out more about it here:

Note: As of August, 2004 this page has been broken (displays a SQL connect error) for several months. Also, if you are lucky enough to find a mirror, you will see that the package has not been actively maintained for several years. If you are looking for a CaptivePortal for OpenBSD, take a look at Wicap-PHP