It is almost as if the premise of the Terminator movie series staring everybody's favorite California Governor is coming true. Finding the cheapest flights and discount airfares is a battle against the machines, as the airlines invest big money in computer programs that maximize the loads; this combined with flight sharing means the days of empty jets is over, this is especially true if you are on a long haul flights, however just like in the movie, their are strategies that you can employ to better you odds.
Get your own Terminator program!
Sidestep, Kayak, Mobissimo, FareChase, FareCast and FareCompare these are programs that work for you to get the cheapest deals. What most of them do is the same thing that Travelocity Expedia and Orbitz do, which is search the databases of the airlines and then they work the margins. The downside of these cheap fares search engines is that most don't have the regional carries listed, so you miss out on the regional cheapest flights. For instance Air Asia almost always has the really cheap flights for $100 or less with in Asia to many Asian cities. The hassle is that you need to deplane and you will need to clear customs and might need to buy a visa and or to pay a departure tax, which can wipe out the savings, but many times the difference makes this a good deal.
Regional flights still offer great deals as they fight for the commuter's traffic and new lines and new competitions cause the airlines to mix it up looking to get market share. Maybe you can take 2 regional flights on different airlines to save money? For instance you can fly Bangkok to Singapore on Air Asia and then took Tiger Air from Singapore to Manila and save a bit of money on that airfare combination.
Finding the Cheapest Airfares
To find some of the cheapest airfares and discount flights look for new airline routes that are going to your destination. Search webpage's and newspapers. The new guy is probably going to give flight deals to get people to switch over to them from their old preferred carrier. The old preferred carrier is going to fight to keep you flying with them, so you win.