Top 5 airline rewards strategies

With an estimated 180 million members of frequent-flier programs and 10 trillion unused frequent-flier miles in circulation, what are the best airline rewards to spend your miles on? If you've done the right thing and accumulated most of your miles with one airline to maximize your redemption power, here's how how you can reap the benefits (or at least try):

Seats. Actual flights are the most popular use of airline rewards, but are also some of the toughest to redeem. Remember the first time you naively tried to redeem miles for a flight and found out that all dates were blacked out, sold out or would cost you triple the miles you expected?

Expiration is another problem with this particular airline reward. In fact, Sen. Charles Schumer (D-NY) recently requested a review of frequent-flier programs for "deceptive business practices" for not giving customers a heads up that they are going to lose accounts or miles. Assuming Sen. Schumer's probe gets nowhere with solving this frustrating airline rewards problem, you need to call way, way, way ahead of your desired days of travel to get seats for the "advertised" miles. And don't neglect to research and manage your mileage program (most airlines allow three years of inactivity before miles expire, though JetBlue, AirTran and ATA only allow one year; Continental allows only 18 months; and Southwest allows 24 months).

Partners. This is where the bigger airlines rewards programs have an advantage. Continental and United; Delta and Northwest, etc., allow you to redeem miles with their partners, which increases flexibility and opportunities to get the flight you want.