More and more independent films are showing that “open source” movies can be created and can have success.
This youtube video shows parts of the footage of a film called The Tracey Fragment. The creators decided to publish ALL their footage to allow other people build on their work (under a BY-NC-SA licence License)
Also Steal this Film 2 was released earlier this year. This film is released into the public domains (so you can do everything you want with it).
There is also Elephant Dreams, a computer generated short film. You can download it and it’s footage.
Find more about this topic on the CreativeCommons Website.