BTW, everybody knows that gasoline is not the biggest use of fossil fuel? Home heating, industry, agriculture all use more than cars do.

I think we'll just start using nuclear power to make electricity for industry and home heating. The electricity would also power cars indirectly by making ethanol or hydrogen, or directly by switching to plug-in vehicles. That's my doomsday scenario. I don't think nuclear is a good "solution". Just the most likely one.