Wasn't POVRay non-linear?
Anyways,Blender is without any doubts the most featured FREE software out there.
GUI warning,very confusing and may get you extremely frustrated if you don't follow an introductory tutorial.
http://www.blender.org/
There's also,Truespace 3.2 that's gone free and is my prefered as far as free renderers are concerned plus it's much easier to learn than Blender.
Get it from Download.cnet.com
If you just want a high quality rendered image for non-commercial uses,the best idea would be to get Softimage Xsi exp(free version) which is shipped with the powerful Mental Ray as well as an awesome,if not the best,built-in Hair creator
Everyobdy wants to be loved,But no one loves everybody...