The following news item is for serious bargain hunters only. Its for readers who are truly dedicated to finding the best fare possible—or who are simply fascinated by how the fare game works.

Although Cheapflights, CheapTickets, Expedia, Kayak, Sidestep, Travelocity, and Orbitz shed a lot of light on low fares, they sometimes miss bargains. None of them list fares from Southwest Airlines, which flies more passengers than any other domestic airline. So no single website offers one-stop shopping for the lowest fares.

That may change next year. Around mid-January, FareCompare.com plans to start offering free e-mail alerts announcing Southwest’s price cuts along with the price cuts of about 500 other airlines.

Rick Seaney, the CEO of FareCompare, recently explained to me how its revamped e-mail alerts will work. Let's say you would like a round-trip flight between Dallas and Las Vegas. You sign up to receive a FareCompare e-mail alert on price drops. One afternoon, you receive an alert on a price drop on the route between Dallas and Las Vegas. Click the link, and you'll be shown a calendar for the next month. On each day of the month, you'll see the lowest fare available. Click on a fare to book. FareCompare doesn't sell tickets itself but sends you to airline websites and online agencies for purchasing.

To understand why this is important, you have to know where the bargains are. Airlines don't always advertise their fare sales. They often quietly drop the prices on selected routes. By industry agreement, these price drops are reported to a central database (three times a day for domestic fares and five times a day for international fares).

Already, FareCompare taps into this database to send out e-mail alerts when prices drop. It e-mails these alerts roughly between two and eight hours before any other source. (It doesn't include Southwest's information in these alerts right now, but it plans to do so starting around mid-January.)

But FareCompare is currently missing a key piece of information. Whenever it learns that an airline has cut its fares on a route, it doesn't know which flights on which dates have those deals. You have to hunt-and-peck on websites to try to find the flights with the lowest fares.

Using its new system, FareCompare plans to point you directly to a calendar that displays what fare is available for actual seats at that very moment on particular dates. Even better, Seaney says his site will include Southwest airfare information in its e-mail alerts in early 2009. Let’s say Southwest has cut its price on a given route. You'll see the lower base prices on Southwest (based on the date of travel and the rules of the airfare) and you'll be able to click through to the "Southwest Shortcut" page, which will likely be a pop-up window from Southwest.com with flight calendar and fare information. This is not a perfect side-by-side offering of Southwest's fares with other airline fares in a single calendar. But it is the first time a site will provide (in two calendars that can be shown on the same screen) fares for a single date and route. It brings consumers a step closer to apples-to-apples comparison shopping.

Price changes on Southwest will also trigger e-mail alerts, says Seaney, something that only Southwest’s own “Ding!” service provides right now.

Seaney adds in an e-mail interview with me: "You can also sign up for price increases. This may seem counterintuitive buy many consumers are procrastinators and want to be notified when sales are about to go away, or when the advance purchase requirements are about to kick in and the traveler must buy before prices go up substantially."

Seaney's goal is for later in 2009 is to offer traditional ticket search engine results with total prices that include fuel surcharges, baggage fees, agency fees, and other surprises. His site aims to provide apples-to-apples comparisons among airlines.

At the moment, FareCompare is having issues with American about how that airline's itineraries are displayed— similar to the dispute Kayak had with American earlier this year. But Seaney hopes to have that sorted out shortly.

Why is Southwest such a flirt? It wants to drive people to book directly on its own website if you want to see a complete listing of available fares you can book right now.

Confused? Sorry. This story is a tricky one to explain because the working product hasn't been revealed yet. Check back with us in January. We'll update you when FareCompare launches its new tool, and we'll let you know if it lives up to its promise of providing the best e-mail fare alerts around.

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