Pixars Renderman software is now available as a free download for non commercial work.
To quote their website "RenderMan is now free for all non-commercial purposes, including evaluations, education, research, and personal projects. The non-commercial version of RenderMan is fully functional without watermark or limitation."
Anyone with any interest in CAD, 3D Modelling and so on will no doubt have seen at least one Pixar movie and looked on with a jealous gleam in their eye. Obviously you need skills and talent to create something like Up or Monsters Inc. but having the best tools available can help a lot!
Now I'll be honest here, I've never used their software before and I'm not that good at 3D modelling and rendering, but I'll certainly be downloading a copy and giving it a try.
Check out the Renderman site for more info.