Interesting question, i was visiting my brother in law in Melbourne last week who is a keen cyclist,he took me down to his local bike shop and showed me the latest carbon bikes($10,000+).
We then watched a guy being "fitted" to a bike he wanted to purchase,his bike was setup on rollers and a computer system setup with cameras and sensors and the guy simply rode the bike and they made changes to the seat post/added longer neck to the handle bars etc until it was setup to his own body style.
It would be very easy to create a fitting system for windsurfing boards and sails! a simple program which takes in height, weight,type of sailing,harness line length,fin size,board volume etc and wind range would help people go a long way in choosing the right setup for the wind range they intend to sail.
People love technology