Necessity being the mother of invention - when oil gets too expensive to get out of the ground, another source of energy will emerge.
Energy being directly proportional to mass (E=mc^2) indicates that the amount of energy available is not the problem. Converting it to a usable commodity is the problem. That's why I've never understood convervation of oil (higher milage autos, solar and wind power etc.) Let's use it up and move onto something better.
$55/bbl crude isn't getting anyone's attention yet. Even Greenspan is saying it's not a problem. I say let's all drive Cayennes, Hummers, Escalades and Canyoneros (Marge Simpson's SUV), use up the available oil and get on to the next source of energy.
Nuclear powered cars would be nice. You buy one and never have to refuel. Insead of a low oil pressure light, there would be a light that came on when you had a loss of coolant accident or a SCRAM. The accelerator, instead of opening the butterfly on the FI, would lift the control rods out of the reactor. If you plowed into a guard rail, instead of a tow truck, you would call a hazmat unit. Obviously there are some problems to work out.
