I used to volunteer at Lake Merrit, in Oakland. They have docks that are made from that recycled plastic stuff that looks like wood. One of the components is a ramp, that is about 6 feet long that has one end submerged and the other tied in to the rest of the decking. Launching is achieved by pushing the boat off the ramp and jumping on as the boat goes flying into the water! In a moderate wind, I was able to sail the Hobie 16's down wind, sheet out right when I hit the ramp, and then jump off and grab a shroud when we hit the main dock, and the boat would pirouette(sp) around right into the wind!
The deck stuff is almost frictionless when you put wet fiberglass on it- One person can easily push a fully rigged 16 around on it, but you must me carefull not to sail all the way accross the dock and into the canoes on the other side!
I cannot imagine a better set-up than having this kind of platform. Mast up, no sand or mud, no alge growth- just 10 minutes to rig the sails and your off! A much better alternative to having my 18 on the trailer, under a tarp in my driveway, thats for sure.