Pixar's Renderman supposedly is going to be free for non-commerical use.

http://renderman.pixar.com/view/registration

"Free Non-Commercial RenderMan is scheduled for release in the SIGGRAPH timeframe, which is August 2014. You will be notified at that time."

Blender3D of course *hust*

Ok, well with this modification it should become quite awesome for character animation soon:

http://blenderartists.org/forum/showthread.php?279052-BEPUik-Full-Body-I...