Next prototype ideas?

Hello there!
well i have returned from Maker Faire Rome with many ideas, too many to compile and put up. but slowly things are turning on in my mind!

here's an interesting site i found:
http://weburbanist.com/2009/03/03/futuristic-strange-concept-bicycles-designs/

and a very very beautiful concept:
http://www.instructables.com/id/Bow-The-Amazing-Bike-Wheel-Bow/

the latter one can be an amazing base for the wheel. So in fact there will be two 20" wheels, for each leg, however one will be cut and bent to fit inside the othere.. the space between the original sized outer wheel and the modified inner wheel wil be fitted with balls to act as a giant bearing!!! interesting isn't it?

solves the problems of load distribution (that was causing a lot of friction in prototype 4) and also the jeans getting stuck in the upper parts of the skate(the upper wheel in prototype 4).

should be light weight too i guess?

another interesting and similar concept:
http://www.toxel.com/tech/2010/03/24/skateboard-with-hubless-wheels/

dont know if its a practical idea, yet.