If you liked the portable aspect of the A-Bike but are too posh to push, then MIT's RoboScooter might be the folding bike for you. Developed by William J. Mitchell and his students as part of the Smart Cities project, the compact bike has two electric motors, one in each wheel, as well as clever integrated suspension, and when collapsed is no larger than a wheeled suitcase.
Recharging is courtesy of a special bike rack, which automatically tops up the RoboScooter's power pack whenever it's hung back up. The project envisions a one-way rental system similar to that operating in Paris (albeit using normal, pedal-powered cycles there), where patrons would swipe a credit card on the rack, take a bike and ride to their destination, then leave it at another rack ready for the next user.
Maybe most useful for long-term viability, the RoboScooter only requires 150 different parts, significantly reducing production costs and maintenance.