I bet if a person went around telling people that someday in the not-too-distant future gas would be $4/gallon at the time when gas was 40cents/gallon, people would have laughed in the person's face as the notion would have been so preposterous.
How about another 10x rise to $40/gallon?
As an aside, G.F.'s kid just got hisself a full-size V8 4x4... for commuting and general tearing around... he's pretty proud of his newly fitted "pipes" too... the price of gas is of no concern, it just is what it is.