http://news.theage.com.au/breaking-news-world/project-seeks-to-turn-car-into-cash-cow-20100219-okvn.html

Someone's worked out that a national fleet of electric cars is:-

a) a huge battery resource for grid peak-shaving
b) a distributed electricity generation system for further peak shaving

Can you image all those cars parked in basements suddenly starting up at noon as the heat rose and the aircon load kicked in?

Of course, this shifts pollution and noise from the big generators to the office or mall parking lot.

Imagine coming back to your car after a day in the office to find that it had burned-up all your fuel while you were away! (of course, you'd get a dollar credit to your account, but you's still have a car with no battery AND no fuel) - though I guess you'd have a smart car that set limits on how much fuel and battery charge you wanted to keep in reserve, vs the price being offered for your electricity...