The new trend here is a wheel off. I completed a folding bike
a la Christian Nau. Needs a larger and real sail (a shower curtain at the moment

), but the mast step works.
My friend bicikite - who usually sails on a two wheels kitebuggy - is going more radical with a completely different and risky design. You can follow his project on
http://www.foilforum.it/covo-smanettoni/carrapaho-t4507.html. Ciao - Enrico