This works for all canceled flights except in cases where it's due to "weather." And even in those cases, make sure it's really canceled because of weather, as I've written about before. (One easy way to do this is to check if flights to your destination on other airlines are also canceled.)

Anyways, once you've told the ticket agent that no, in fact, the weather at your destination is a sunny 85 degrees, here's how to avoid sleeping over at the airport or standing in a line for the next six hours.

It's known as Rule 240. Just mentioning this little-known clause to the ticket agent may open doors. But here's how it really works: Rule 240, a remnant of the days before deregulation, stipulates that your airline must book you on another airline's flight if that is available and will get you to your destination quicker.

The great news is that most airlines, at least the ones that have been around before deregulation, still honor Rule 240, though it's not officially valid anymore. Only the new airlines like JetBlue, Southwest, and Air Tran refuse to honor most of these requests. Just remember, make sure to actually say the words "Rule 240" the next time you're at the counter.

Filed under: Airlines, Airports