Wow, that really is a nifty gadget. Note that it won't work very well in dry climates though. Also, it would be great to combine it with a room air conditioner, basically mounting it in a window so the heat exchanger is outside and it cools the room while dehumidifying it.
I've been wondering for a while whether there's enough humidity just above the ocean, to be able to condense fresh water out of the air by pumping it below the ocean surface for cooling, without having to mess with mechanical chilling.