For those road warriors out there with a lot of frequent-flyer miles piling up, a saner way to figure out how to use those miles is ExpertFlyer. On the site, you can check regular seat availability for 400 airlines, and award availability for a smaller selection of major airlines. This feature was relaunched in April with an updated, easy-to-use tool. The U.S. airlines the award-seat feature supports are:

Alaska, Airlines
American Airlines
Delta
Frontier
Northwest
United (just added)

It can also check award status on the following international airlines:

Aer Lingus
Air Canada
Air China
Air France
Air New Zealand
Air Tahiti Nui
British Midland
CSA Czech Airlines
Qantas
Shanghai Air
SWISS Air.

You just put in your flight and it tells you how many award seats there are, for each different class of award. The site lets you set up an alert for when award tickets become available on a particular flight. I just wish it didn’t cost $5 a month. But enough hardcore flyers are willing to pay the subscription that the site became profitable seven months after it launched in January 2005, says co-founder Chris Lopinto. The company has not taken any VC money.

They tap into the same global reservations systems that travel agents use and are charged for each query. But Lopinto is now exploring the possibility of launching a simplified version of ExpertFlyer that would be free, focused around providing seat availability for award seats and discounted Y-class fares. That probably won’t launch until nextyear, however. So for now, you have to pay.