almost four years ago, when oil was trading at around $40 a barrel, Paul Roberts wrote a story for Mother Jones on a bleak scenario gaining currency among energy insiders, but not yet in the mainstream consciousness: peak oil, basically the notion that the world's petroleum resources are nearing exhaustion. If the theory held true, Roberts warned, oil prices could soon leap to "perhaps as high as $100 per barrel—a disaster if we don't have a cost-effective alternative fuel or technology in place."

read the rest here at Mother Jones.