ParaDB is a web-based (PHP/MySQL) application designed for use by ghost hunters and paranormal researchers. The software consists of a web-based interface for case management, client relations and investigative reporting.
Very extensible and customizable. I like that it can be installed stand-alone (With WAMP of something similar), or in a webhosting environment.
ParaDB is an extremely useful and robust tool for paranormal investigation teams. It does have its share of bugs and development is a bit stalled, but it is still the absolute best out there, hands down for what it does. I'd love to see more PHP devs take an active interest in improving this...