If you head over to Wolfram Alpha right now and input "flights overhead" into the search box, the site will return all the planes that are currently over your position, their altitude, angle, and slant distance. The site even displays a Sky map to show where planes are in relation to the position of the sun and moon.

But if you want more usable data, like where the planes took off from and where they're going, simply click on one of the flights, and you'll have all the information you need. Plus, you can see a map showing where the plane is currently, and what its flight path will be. Note that the information is five minutes old because the Federal Aviation Administration, which provides the data, builds a five-minute delay into its feeds.