Anyone interested in a free surfboard design software program. I just downloaded one and it works pretty good. Also has a cool 3d veiw of the board you have created. Now if I can find a way to run the designs thru a waterflow simulator. Check it out its fun to experiment with. http://www.shape3d.com/ http://www.shape3d.com/ 
I’ve done a fair amount of CFD work - unfortunately to get good results it takes a PhD, a $250,000 program and a years time. I was toying around in a little elementry program called FloWorks - it piggybacks on a 3D modeling Program called SolidWorks. Unfortunately SolidWorks doesn’t make it easy to really get a good surfboard shape that you can manipulate - the rails are tough. They over simplified - which can make it the easiest 3D modeler of all time, but can also make it the most frustrating if it doesn’t want to do what you want it to. If you do end up with a good model you can spin it around in 3D space to you hearts content, you can even mask on JPG’s if you’d like (or they make a program called PhotoWorks to add textures and such) once you have your model your a few clicks away from running a CFD analysis. But, like I said, this is an elementry CFD program, and it makes some pretty big generalizations on the Navier-Stokes Equation - the results are far from perfect… but the only true way to test a design is to build it and surf it.