Q. I've never been able to find an airfare website that allows me to enter specific dates that I'm available to travel, such as leaving Nov. 12 and returning Nov. 18, and then shows me a list of the cheapest fares to anywhere leaving from an airport I specify. There are sites that show the lowest fares to various destinations from my local airport, but not according to the exact dates I specify. Why is that?

A. I've received many requests here at Airfarewatchdog for just such a website. The only reason I can think of that one doesn't exist is that it would take a huge amount of computer processing power. If you've ever waited for an airfare result between specific cities on specific dates on sites like Orbitz, imagine how long it would be to sort out an up-to-the-minute list of fares between every possible city pair on every possible combination of dates. I'm no math whiz, but the number of iterations would be enormous. Maybe some computer genius reading this will figure out how to do it.