This is a great new feature that allows you to research the web, find images, and quotes from inside of a Google Document. Check out this video for more information and classroom applications:
For more information on this new feature check out Google's Blog on this topic titled: "Find Facts and Do Research Inside Google Documents."
Another great source is one of my new favorite blogs, Free Technology For Teachers. He also has a post and some great screen shots as well titled: "Search the Web Within Your Google Documents."
Way to go Google! Keep the new features coming.