Forbes magazine writer Christopher Steiner has set up a useful heuristic device--the escalation of the price of oil in two-dollar increments, from $4 to $20--to speculate about the changes in our lifestyle we might see at each stage of the price increase. At $4, some of the tougher choices might still be unpalatable, but with the continuing increase in price, more radical changes will become necessities, if we are to survive as a civilization at all. Others have written much in the last few years about peak oil scenarios; the most persuasive such analyst has been James Howard Kunstler, particularly in The Long Emergency: Surviving the End of Oil, Climate Change and Other Converging Catastrophes of the Twenty-First Century (Atlantic Monthly, 2005).