We built this at Yahoo! in summer 2007 after the FareChase acquisition. Took about a week or so to prototype, and a couple months to offer various filter/search

We built this at Yahoo! in summer 2007 after the FareChase acquisition. Took about a week or so to prototype, and a couple months to offer various filter/search criteria and prepare for launch. With access the good flight data APIs it's a pretty simple app. Of course for us it was never allowed to launch. Glad to see Google was finally able to push something like this. Main feature missing that Y! Faremaps had is the ability to specify a span of time in which you wanted to travel and the cheapest trips in that timeframe were shown. Also, you could search "weekends only" in that timeframe.