Taskjuggler
"Taskjuggler": http://www.taskjuggler.org/
Taskjuggler is probably the most comprehensive project management tool freely available.
It consists of a backend program that takes input files and generates reports. The are a couple of graphical editor programs with it, but they are more like IDE's. You need to learn taskjugglers language to create projects.
** Pros **
- The most comprehensive project management software.
** Cons **
- Own input language discourages editing by others.
- Some work to hook into our web site perhaps - depending on how we wanted to use it.