There's nothing the matter with conservation and efficiency. I think that only a fraction of people will do it, but they will be the ones that can live within their income, while the yahoos with their giant pickups end up living in some trailer somewhere freezing in the dark, unable to go anywhere because they can't afford the gas.
The car of the immediate future is the hyundai accent. It's a completely inocuous car which is cheap to operate and can be bought cheaply.
Without credit most people won't be able to do much to their houses, so the only thing they can economize on is transportation. They might have a big pickup now, but when the economy tanks even worse next year they'll send it to the knacker.
This depression is hitting men far worse than women. Men drive the pickups. They will be back to riding shanks mare soon enough.
If they are lucky and smart they'll become insulation contractors and keep the truck for real work.



