About a year ago one of my Maui kiting buddies pulled this gizmo out on the beach and launched on a very light wind day. We were dubious he could even keep a kite in the air. To our amazement he could even kite upwind. It had great light wind performance that rivaled a foilboard. The activity is called seagliding and you can learn more about it here.
Air Sailing the Seaglider in Maui from Jon McCabe on Vimeo.
http://seaglider.fr
And here is Damien Leroy filming his sessions on the SeaGlider from a number of different perspectives. This gives a better idea of what is going on.