The Economist has its Big Mac index of purchasing power; I, food snob that I am, have a sushi index....

The Economist has its Big Mac index of purchasing power; I, food snob that I am, have a sushi index. And New York, by that measure, is off the scale. In most cities, sushi is sold in pairs. I was surprised by the fact that a maguro sushi seemed no more expensive in New York than in San Francisco. Until I realized that, in Manhattan, it's not just the apartments that are tiny: the sushi comes in singles. In New York, people turn to their waiter and say, in a tone of MacDonalds enthusiasm: hey, would you mini-size that for me?