Carbon-free, stackable rental cars

Combined with a sustainable supply of energy for recharging, the stacked-rent-a-car idea looks really appealing. Although mass public transport is superior, this could provide a stepping stone in the right direction. Especially in cities such as Auckland which have such a car-centric infrastructure already in place, it could be the key in convincing people to rid themselves of their metal beasts. I for one would find this a huge help (and most likely, very economical). I could sell my infrequently used car and save myself all the associated maintenance & running costs but still have access to such a mode of transport.

A group of researchers at MIT have been hard at work developing a solution that's kind on the planet and your scrawny legs. A team called Smart Cities have designed a small, two-seat, electric vehicle -- which they call the City Car -- that can be "stacked" in convenient locations (say, just outside a subway stop), and then taken on short trips around urban areas. The cars -- which are based around an omnidirectional "robot wheel" that encases an electric motor, suspension, and steering -- can be "folded" and attached to a group of other cars for charging. The lineups of rentable vehicles would be accessible from various points around a city, with six or eight cars occupying just a single "regular" car space

Via Engadget. See Technology review for more info.