Soon you will able to get a total body workout while walking on water with the TU FiN fitness boat. The TU FiN works like other 'track' walking exercise machines, but the mechanism has been placed inside of an ultra-sleek boat.
The energy you create from working out is transferred through the bottom of the 26 foot boat to a couple of fins which project out of the boat's hull. The fins, which look like duck feet, flap and propel the boat up to speeds of 6.5 knots. There is plenty of room at the front of the boat for provisions and even a passenger.
TU FiN was designed by a group of German students for a competition. Although the working prototype don't look quite as sleek as the concept, I trust the production TU Fin will be really cool.