John Batelle has a great writeup of a new service called "Farecast" that uses historical pricing data from the airlines to predict what the best time will be to buy a given plane-ticket. The service is in private Beta right now and only works for Seattle and Boston, but they're promising a full launch later this year with all cities covered. Man, I so need this — I fly all the time and I get royally screwed by the airlines.
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