A T-Pod for your iPad
I can see this thing becoming a "must have" item for cruising sailors. It's designed for fishermen, but its utility for getting around in shallow or turbid water could save you a lot of grief—if you are the type that goes poking around in shallow water.
You put this little 4oz. "bobber" on a fishing pole and cast it out around the boat and it transmits a wifi signal to your iPad that gives you a reading of the bottom contour and depth of water.
Neat!
/fl