Re:Apps? (Score 1)

Last I heard, Pixar at least uses Maya, which is proprietary but gives out some pretty good crippleware for free (the "learner's edition" has a full featureset but watermarks rendered output.

In fact, Pixar has released a couple of its own plugins

It, incidentally, runs on Windows, Mac, Red Hat and SUSE.

Of course, they don't use it exclusively. I was delighted to notice that one of the heros showed briefly in The Incredibles had a POV-Ray logo on his costume. POV-Ray is halfway open-source (not GPL, modification allowed only for the purpose of porting or adding to the feature set), but it's much better for still images than animation because it renders frame-by-frame (see povray.org for more and some very shiny examples)