If you're on the look out for other collaborative projects to work on here's a few good places to start looking.
This is a site started by our friend SoftDistortion, who's been extremely supportive of our film over the years. He's setup an entire infrastructure for posting projects and running them. There's also a number of film projects running on it, both publically and behind the scenes. It's well worth signing up just to see what's going on and make yourself know to the community.
This one is run by David Andrade, who also recently finished his short film 'Nuts for Pizza' on this collaborative site he started a few years ago. Like the one above it includes numerous features for running most of the project. You can post new projects on there or sign up as an artist to find a project to get involved in.
Of course there's also these two well known sites offering a section dedicated to projects like this. They're just threads but they're both good places to look around to find other interesting projects.
Another project that doesn't seem to be in any of these places is Them Greeks.