Google flight search is awesome!
Google Flight Search is a tool to shop for flights and fares at a speed of thought.
I remember a couple years ago I was recommending all my friends a flight search on a small website called itasoftware.com. It would quickly output the best prices for fares even when you select many options and I used that service to book tickets to a few places. Who knew that two years later, the small company would be acquired by Google for 700 million dollars! (http://www.google.com/press/ita/)
I guess it was expected from Google to make use of this new acquisition so Google now has an amazing Flight search engine available for anyone to use when searching for US flights.
Check out the flight search that just flies !