Blogpost: http://pleasantsoftware.com/developer/3d/2010/03/01/pleasant-future/

Download: http://www.pleasantsoftware.com/developer/pleasant3d/index.shtml

Yes, it is only available on Mac OSX.  But now you have a reason to buy a Mac.  I could not believe how much better this looks than all the other software I have used.  I am just now digging into it, but from the blog post and the videos, as well as playing around with it on my MacBook…. it looks FAR SUPERIOR.