With the Schiller X1, cyclist becomes seafarer (bbc.com)

With the X1, the upright cyclist becomes seafarer.

Recumbent cyclists became seafarers with regular pedal boats ages ago.

Pedal boats are nothing new; Leonardo da Vinci had drafted up a concept of this already.

The new thing here is the rider position and minimalistic construction.

This seems more useful:

http://www.shuttlebike.it/