One of my long standing goals is to always pay as little as possible in airfare. The latest tool to achieve that end is Farecast which tracks airfares over time and lets you know if you should buy tickets for a trip now or wait for prices to drop. There’s a lot of received wisdom about when you should buy tickets, but Farecast uses quantitative analysis to make predictions about how to best time your purchases.
I’m anxious to apply it to my future ticket purchases. (The search interface is really nice as well, comparable to the one provided by Kayak.)
On the other hand, given the idiotic flight security rules, I’m not exactly eager to fly at all.
One thing I’ll be interested to observe is whether Farecast will end up being a force for change in how airlines price their tickets. Airlines profit through obscurity, but Farecast could wind up making the pricing strategies of the airlines more transparent.