Electrical Battery (sounds more like a Capacitor) for tomorrow.

If this turns out realistic....

http://money.cnn.com/2006/09/15/technology/disruptors_eestor.biz2/index.htm

But, we need to make sure to feed the power grids with non-CO2 ways to produce electricity, mostly nuclear or eventually fusion!

Update: May 2009 - does not seem like they got very far in almost 3 years...