This little guide has saved my rear at least twice a year, over the last decade and a half. The most recent renewal cost only around $53 (a special deal last fall, highlighted by a Flyertalker!), and I'd subjectively place its utility value at six times as much.

Yes, my laptop can gather the same data, but finding a place to plug it in is often difficult. FYI, as of the January issue, they have added listing for flights from N.A. to numerous large foreign cities (Tokyo, London, Amsterdam, Frankfurt, Paris).