One of my favorite Google Earth apps is FBOWeb's commercial airline flight tracker (review). Enter in the details of a commercial flight and you can see exactly where it is. If you're a real geek, with Google Earth's new built-in flight simulator, you can also zoom into the flight and see what it'd be like to fly it youself.
The easiest way to access this feature is to just type in the flight code in Google. For example, search for "AA 34" (American Airlines flight 34), and click on the "fboweb.com" … Read more