The Body Geometry stuff is really good, supposedly. I tried on some shoes when I was looking, but they didn't have what I'd want (1-2 steps up from the bottom) on clearance at the Specialized LBS, so I had to pass, but they fit great. One thing that I tried didn't fit well at all, leading me to believe that with entire lines there should be something. It looks like Specialized has a BG Saddle Fit system that is standalone or in conjunction with the BG fit... as I'm sure many others do as well.
My fav saddle was a Fizik Pave that is long gone, and probably too small for me, but a tiny little road bike saddle on the mtn bike worked great.
**BRENT**