Indeed an invention that seems stupid, but 10+ years ago, there was this article in American Kite about these 2 french brothers who designed an inflatable "sail" that lofted itself without a mast and was sailing a catamoron with it. They called it the Wippacat. It was neither eligant, or did it offer better performance than a regular sail or a ram air power kite (which I was land sailing with at the time). I dismissed the whole thing. This stupid "sail" eventually took to flying on lines like a kite and evolved into the Wippika and its derivatives from Naish, North and Cabrina are now the staple power kite for the kitesurfing banaza. My ram air kites will still out fly, out pull, out run and out jump any of these "blimps". But damn it, everyone except a few dedicated maverick pros are flying those wippiabortions. Those 2 frogs are rolling in whatever currency they are excahnging these days.