I'm looking for some kind of project management solution for animation.
The people involved are located at different places so we need some web-based solution for managing the project.
An easily overviewed interface where I can set up each scene with descriptions, timeline, who's animating it, adding some sketches, some video and other reference material etc. Where everyone involved easily can add comments, content etc.
It would also be great if we could easily exchange project files via the interface, animation files, source images etc., but I already have a FTP so we could use that for file transfers.
We will be working on Linux, Mac and probably some windows-machines as well so the solution needs to be platform independent, preferably web-based without having to install any software (except perhaps on a server, which would be a linux-machine).
I have been thinking of setting up a forum or a wiki for the project but those solutions would be rather crude for the task.
I have also googled for project management software but all I've found seems to be ill-fitted for animation/film-projects.
I would also like the solution to be open-source, or at least not very expensive.
Any ideas or suggestions?