Great article in Forbes on the smart garage concept going to market in two years or so. The idea behind smart garage is that people drive electric or plug-in hybrid vehicles that we not only charge up at night, but also sell energy produced by the vehicle back into the grid. The consumer will also be able to specify what type of electricity they want to purchase for their vehicle, for example, solar and wind only. The article explains it better than I can here, definitely worth the read.
More on the smart garage concept here at RMI Move, the folks that developed it.