Although the inventor seems a little stressed out ("Please do not email me") he's made a pretty fantastic thing, so we're going to cut him some slack. The 'Hydro-Foam' R/C vehicles are currently prototypes, powered by a brushless motor and lithium-polymer batteries. What makes them so special is their ability to travel not only on the water, but through the air, and on the ground at serious speeds. And this isn't a 'park it and swap some parts thing.' The videos show the Hydro-Foams moving from water to air to ground and back again with just a flick of the flaps.
They definitely look easy to destroy—creator Michael Connally's website makes it clear that this is "not a beginner airplane"—but they will be available for purchase sometime in the future (sooner if you'd just leave Connally in peace). (Thanks, Spinelli!)