If you're a Virgin America frequent flier, your points could be worth more than you think. In an example of cross-marketing that would make a Harvard MBA proud, the airline is allowing passengers to cash in their miles for the chance to win a seat on a Virgin Galactic space flight.

Virgin says it'll work like this: Earn 10,000 points in Elevate, the airline's frequent flier program (it might take awhile, as the airline flies to just seven cities) by next July and you can sign up for what Virgin America calls "The Race To Space." If you opt in, you'll participate in a "series of competitions" – the airline isn't saying anything about them yet – that allow you to earn more points. Finish the challenges with the most points and you're going sub-orbital when the WhiteKnightTwo unveiled this week takes SpaceShipTwo into space in 2010.

It's a cool twist on frequent flier miles in an industry that is choking on them.

There are 17 trillion frequent flier miles out there, making them one of the most circulated currencies in the world. Henry Harteveldt, an analyst with Forrester Research, told Wired.com that as more and more them pile up in people's accounts, they become worth less and less (think Germany after World War I, when the government printed so much money people started wallpapering their homes with it).

These miles are a huge liability on airlines' balance sheets, so they'll do anything and everything to help customers get rid of them. They're partnering with anyone who will have them, striking deals that allow passengers to drain their accounts by buying just about anything besides an airline ticket. "Airlines need to sell seats, not give them away, which is why there are all these partnerships out there," Harteveldt says.

You can use your points for virtually anything. Get a hotel room, rent a car, take a cruise. Use them for vineyard tours, seats at ballgames, backstage passes for concerts (Celine Dion, anyone?). You can donate them to charity, pay for a class, or exchange them for a bundt cake from the Dessert of the Month Club. And now, vie for a trip to space.

Image: Virgin Galactic