Ride On: Not Quite Bikes

Bicycles get a new twist with these innovative designs for land and sea. ItBike (above) won't let you walk on water--but it will let you glide gracefully on the surface. It's sturdy enough for the adventurous among us to give it a go on moderate ocean waves. Those who prefer a smoother ride will fit right in among paddleboats in calmer waters.

T8 Convertible Air by Trikke (left) skips the pedals but keeps the handlebars, producing a carving, skatelike ride. The latest model has air-filled tires and a lighter frame (20 pounds), making it easier to carry in your car or on public transit.

Aquaduct (below) won Google's Innovate or Die Pedal-Powered Machine contest with this prototype for a "water-filtration vehicle." Designed for locales with limited potable water, the tricked-out tricycle cleans water with every pump of the pedals and provides an ample storage compartment. Not yet mass-produced.