This is a reply to an earlier answer,
They also said that in the 70's.
It is true that we will probably run out soon. But there is no certainties. In the 70's the majority of the people were sure that there would be none in 2000, but as you know: there is.
In the 70's-80's the cars made more then 30 miles to the galleon, or they wouldn't even advertise the miles to the galleon ratio.
Now that cars are heavier, they therefore use more gas.
They should make cars lighter again, and even being softer would help greatly on multiple levels.
There are cars that run on natural oil, meaning oil made from lima beans I think it was. A taxi driver we met one time outside of a 7-eleven had this, as well as a tractor-trailer we saw once.
This is a completely biodegradible solution to our problems. More people should use this system.