There's fractal generators and there's 3D modelers and there's XenoDream, which is both. I'm probably going to buy this as soon as the next dot release drops (will make it Vista compatible).
http://www.xenodream.com
There's no demo, but take a look at what artist Joseph Presley can do with it:
http://fractart.net/FractalAbyss/XD10/XDpic227.htm
(hit arrow for next image)