Yes I know..It is not windsurfing...and
I was reading the log from PUMA on the Volvo Round the World race (sailing).
Thought this might interest some people
Have a look at the top speed and the averages..... very fast

(44knts peak on a 70ft boat....crikey)
PUMA LEG FIVE DAY 3 QFB: received 16.02.09 1206 GMT
I think our average wind speed so far this leg has been in the mid 20's and we peaked out at 44 knots while reaching through a small group of islands just south of Japan. That was fun.
Sitting below staring at the computer, making calls through the deck com system as to what we should expect next with regard to wind strength and direction, all the while navigating through a small gap in the islands and stepping into the Kurishio Current (this part of the world's Gulf Stream) which runs at about four knots. Oh yes, in a pitch black night while travelling at an average boat speed of 25 knots in bad seas! Would make for great NM speeds
cheers
Climber