In 2004, five middle-aged techies in Dallas set out to crack a system that has frustrated and mystified even the savviest consumers and number crunchers.

Working 12- to 16-hour days for more than a year, they fought through code that had been extinct since the 1980s and endless mounds of paperwork, paying a million dollars for the privilege of mere access to the database they were picking apart. Small epiphanies kept them pushing to the next page of code; an endless string of technological knots made clear why no team before or since has duplicated their feat.

Finally, FareCompare C.E.O. Rick Seaney and his partners quietly lifted the curtain from the single database containing the world’s airfares, making available comprehensive, real-time access to the 160 million new ticket prices reported each day. If this sounds like a modest payoff, consider that not even the airlines have the software to monitor global prices in real time like Seaney’s can. When time is of the essence—whether for travelers hunting for deals or airlines reacting to competitors’ prices—FareCompare has a monopoly on insider information in the airline industry. Their work resulted in a series of surprises, the most recent being the ire of the airlines and the intense interest of hedge funds.

In the beginning, FareCompare, then XXI Technologies, used this advantage to consult for airlines and travel companies. After 15 years of mining data for oil companies, Seaney and his chief technology officer, Graeme Wallace, were working on a project for Hotels.com that introduced them to the bizarrely complex world of airfares. They took the same fare database that the airlines and all major travel sites subscribe to and created software that can run enormous price queries faster than anyone else. When Expedia bought Hotels.com, it scrapped the software that XXI developed. But the programmers believed their product was unique and decided to strike out on their own. Now FareCompare posts new fares an average of five hours before they’re published on any other site, including Expedia.

In March 2006, XXI switched its focus and its name (XXI is still its holding company), becoming a consumer site that promises travelers with flexible departure dates that it will pinpoint the best-priced flight possible. But FareCompare’s most recent incarnation has been its most unexpected. It’s not just offering a reliable way to save money on air travel, as the average consumer may think. FareCompare has also become a provider of alerts and trend reports to airline-industry analysts hungry to understand the pricing moves of the companies they watch; its information is coveted by investment banks and hedge funds; and it’s a thorn in the side of the airlines themselves.

Unlike nearly any other industry, airlines sell products that can shift hundreds of dollars in price within minutes. Discount travel sites have become the consumer’s guide to navigating this fare zoo, and travel is the biggest online market there is, grossing $81 billion last year alone.

This has been the busiest summer for domestic travel since 2000, with planes packed to 90 percent capacity. Seats are scarce, and prices are high. FareCompare helps ameliorate that, to an extent. Though the company can’t guarantee travelers that a flight they book one day won’t go on sale the next, in addition to giving customers the best currently available price, FareCompare’s route-specific maps of fare history dating back three years also give them a sense of what they’re paying for.