I can't say I'm a huge traveler -- even though I've hit up quite a few conventions this year for work, I haven't been flying so much that I need to keep tabs on what's going on at the airport. But I like the idea of FlightBoard anyway. It's an app that will automatically create a departing flights board for any airport in the country, so you can see flight numbers, gate arrivals, and departure times for all the flights in the airport.
Like I said, I personally don't fly enough that I'd necessarily need an app just for this, but if you find yourself running off to the airport a lot for a certain reason, this app seems like it would be very helpful. Even beyond the specific function, I like the idea and design of FlightBoard -- it's modeled after the flight board at Charles de Gaulle airport in Paris, and it is terrific example of how an app can successfully use an interface metaphor. In the real world, flight boards are often just a standard LED display (or, more recently, a series of monitors). But in this case, the app represents the idea of a flight board, so it recreates the LED display, and it makes the information more familiar to the user. We've all seen and used a flight board, and this app benefits from that previous experience in its interface.
In any case, that's just some interesting UI design insight. If nothing else, this app will tell you when and where planes are leaving at whatever airport you choose. FlightBoard is on the App Store right now for US$3.99.