How high can crude prices go?

Looking at the inelasticity of demand, I have to wonder whether triple-digit crude oil prices aren't undreasonable...We're 2/3 of the way there.

Oil continued to beat gravity Friday, shooting past $66 a barrel as traders continued to sweat a scarcity of worldwide production capacity.

September crude surpassed Thursday's high and was recently up 32 cents to $66.12 in electronic Nymex trading. The contract settled at $65.80 Thursday, its highest close ever, after a private consultancy said non-OPEC production growth isn't keeping up with global energy demand.