Overbooked flights are becoming more common. The number of people bumped from a flight jumped 24 percent from January through September last year (the latest statistics available from the Department of Transportation) - but if you have some flexibility in your schedule, you can score free tickets and some nice perks in exchange for giving up your seat.

When you get to your gate, ask if the flight is overbooked. If it is, ask what the airline's initial offer is and get on the volunteer list. Being on this list doesn't obligate you to take what the airline is offering; it just gives you the right of first refusal.

If you don't like the compensation package, decline it and either stay on your scheduled flight or see if the package increases when the airline makes an offer to your fellow travelers. This is your chance to hold out for big money, since gate agents can sweeten the pot until they get enough volunteers.

Also, keep in mind other flights that are headed to your destination, including connecting flights and flights to neighboring airports (they may be more convenient than what the airline suggests). If you're offered a free ticket, ask if it has any restrictions, like expiration or blackout dates, and make sure you get a confirmed seat on your next flight - you don't want to give up one seat just to get involuntarily bumped from another.