Morgensen generator; that sounds better than the name I was using (I didn't know what else to call it), but it's what I'm using. You don't need a Mac to use it; I'm using a plain-Jane AMD64 (OMG! only one core?!? ) and it works beautifully. However, I'm not sure it would run on a Windows platform- I use Debian to get things done. If you want a copy of the source code, I'll be more than happy to PM/attach a copy (as far as I can tell, the source code is GPL liscenced so it should be ok).

I snagged a copy of Fractal Terrain Pro and am giving the interface a shakedown. It's interesting (and certainly worth the investment), but it so far feels less flexible.