We love to share, and we do so with Creative Commons license. Ton was recently interviewed about this (and Llamigos!) on the Creative Commons blog.
Open licenses are essential for sharing our films and their source material. CC BY and CC 0 make the asset collections usable for other projects. Also, for the kinds of training that we want to encourage, it’s essential to give students the right to build on top of our work in order to make new works, share those works, and show them in public.