I just came across this handy software called "G" Thang ... it's a program that lets you plug in all sorts of guitar building parameters and it helps come up with a shape. It also lays out fret positions and exports to a DXF so you can bring it into a CAD app and use it to make your shop drawings or jigs or send to a CAM app to do CNC toolpaths.
I dunno how many are interested, but i found it nifty
Check it out: http://liutaiomottola.com/formulae/gthang.htm
Oh and also on that site - i have learned the magic number is 17.817