As a city car I'm impressed by the Renault Twizy (it's a 4 wheel bike). Okay, so the power output and range are much lower but for shorter commutes when you can charge overnight it seems to make a lot of sense. Relatively cheap too, although you do have to factor in the cost of leasing the battery pack. http://www.renault.co.uk/cars/model/twizy/product.aspx