If your itenerary is flexible, it is very possible to save a good deal of money by allowing your flight search on websites such as TripAdvisor, and popular travel sites like Expedia and Travelocity by being open to leaving from nearby airports. Sometimes nearby airports, since they tend to be smaller than the main international airports, get less traffic, thus using them can save you time and promoting them is beneficial to the airport and airlines that use them. Allowing for a longer drive time (sometimes as much as a few hours) can also save you a lot of money.
We were just researching travel options for Christmas on Tripadvisor from Dallas to Mexico City. The cheapest round trip flights from Dallas to Mexico City on several airlines were over $750! They ranged all the way up to and over $1,000. Keeping in mind that the normal price for this ticket is around $350, give or take $100 depending on the season. We've never paid more than $450. I was shocked and really began to consider taking the bus. However, when I tried the same search from San Antonio, I found the tickets to be significantly cheaper. The ticket average was about $500. This would save us about $500! Granted we would have to drive a good four hours, however, $500 is $500 and leaving your car at one airport is not much different than leaving it at another airport. Tickets to Cancun from Austin, (a three hour drive) as opposed to Dallas were less than $200 on Viva Aerobus Airlines.
Although it may not be the fastest, it just might prove to be the most economic way to fly this holiday season.