whodawannahuh?

Every sinceI first heard of laser propulsion many years ago, I became fascinated with the idea of it. Lately my interest has been rekindled and I have been looking up information in my spare time. The idea of laser propulsion is fairly simple. A ground based laser shoots a beam of light to a craft whose bottom is highly reflective and focuses the light. The focused area is heated up to such a degree that the air is converted to plasma and causes a miniature explosion. This explosion is what causes the propulsion. Nifty huh? The original purpose of this concept,was to launch cheap lightweight crafts into space, to this date that hasn't happened. My question has always been, and what interests me about it, is why limit this propulsion system to just space launches. What about putting a system like this on the back of a boat and having the laser push the boat along? Obviously there are some problems with a laser propulsion system, intense heat and the need for a 10 kw laser. If work could be done to lower the power to about 1 kw this means of propulsion would become more feasible for alternate forms of transportation. I'm hoping to put some information together for myself and possibly try to contruct such a device. I'll keep you all posted if anything comes about.