I think if we did decide on a collab project it'd be best to start out small.
A still image depicting a set idea or design. Each member who signs up for it creates a small model or part of the image, or brings them all together for rendering or something along those lines.
If the project proves itself then move onto bigger things such as animations + productions.
What would be cool though, is team challenges, where say 6 people form a team and create an image/animation against another team of 6 people.
That'd be sweet.