100 MPG in a converted Toyota Prius?

This article talks about supplementing the battery pack of current Hybrid Electric Vehicles by adding your own batteries. The scary part with all the recent talk about exploding Lithium based cells is that at least one company's solution is a 150-pound, 16-inch-by-33-inch box of lithium-ion batteries that fits in place of the spare tire.

That said; I want one! It wouldn't be very practical right now and certainly wouldn't save me any money, but I'd sure have a lot more stuff to play with as I drove and maintained it. Maybe I should just see if any of the DARPA Challenge vehicles are up for sale instead...

How about this electric vehicle from Tesla? They claim 250 miles per charge and 0-60 in 4 seconds for somewhere around $100,000. People are talking after Engadget posted an article this morning .