The imminent arrival of peak oil, or the point in time when the maximum rate of worldwide petroleum extraction has been reached and enters into a continuous decline, has long been regarded as a fringe theory. As oil prices have crept up in recent years, the concept has gradually entered the mainstream--and now the International Energy Agency, an intergovernmental organization that offers energy analysis to 28 countries, has announced that peak oil passed us by in 2006. There is nowhere for our oil supply to go but down. So what do we do?