RE: MIT's radical proposal for an ultra-compact, foldable electric vehicle
What about a ski-lift gondola type of approach? Platforms could be above street level, no parking issues, no battery recharging, no need for sophisticated folding geometries, individual gondolas would be much cheaper than these independent vehicles. Subway (mass transit) stops would be hubs, with lifts radiating from each. The issues of multiple stations and of acceleration/deceleration onto the main cable have already been solved.
BTW: 20 megawatts does not charge the city of Boston for two minutes. Perhaps 20 MW-hours is the average consumption in two minutes, but that translates to an average power demand of 600 megawatts. Please take care in distinguishing between quantities of energy and energy flow rates.