Brilliant animation, just dont try to follow the plot.

All done with open source software:

http://www.elephantsdream.org/download/

Quote from: maximusotter90% done with open source software:

They had to use Reaktor for the the sound/music.
http://en.wikipedia.org/wiki/Elephants_Dream#Software_and_tools_used

And it ought to have been called Proogs Dream, wouldve made a little more sense for the first-time viewer.
Still an excellent demo for OSS/Blender....Jeez the interface for that thing scares me.