For years, airlines have priced individual seats on different days at different levels. This can drive you nuts, if you're trying to get a good deal. It can lead to situations in which you turn to the guy on your right, and ask him what he paid, and find out he paid half what you did - even though you bought your ticket earlier than he did. It's time to fight back!

Farecast is an airline fare site mentioned in Super Crunchers. It's the best travel site for finding fares I've seen. Amazingly, once you've searched for your travel dates, it offers it's own solution and then also offers direct links to nearly all it's competition (Expedia, etc). But at least in my testing, it always beats that competition in price. That's not the real reason to use it, though.

Once you tell Farecast where you're going and when you want to go, it also predicts whether the lowest fares will rise or fall in the next week. It's using science, rather than marketting, to find fares and make these predictions. It monitors and evaluates pricing patterns of nearly every airline as they tweak their own pricing, and predicts what pricing will be over the next seven days, based upon the history over the past 30. It's smart enough that it can even give you a confidence level of how good those predictions are likely to be, and shows you a recent history of where prices have been over the last 30 days, so you have a sense of what this might be worth to you.

I've seen it predict a round trip ticket between Seattle and Washington, DC for $200 (it found this by sending me to Baltimore, a short drive away), for a flight one month in the future, with a warning that prices were going up. I couldn't buy right then, so I had to wait, and sure enough, a week later, prices were $360! (It then told me prices would be stable, which they were). You have to be careful, though - while prices may drop in the seven day period, they may do that for only a short period - perhaps only a day.

When you use it, be sure to check the box to have it look at nearby airports - that's often how you get the best deal!

Microsoft must be impressed, too - they recently purchased Farecast!