Google Earth has a built-in flight simulator. It helpfully offers to start you out at Kathmandu for some exciting views of the Himalayan mountains.
Google Earth flight simulator
To load the Google Earth flight simulator, type Ctrl-Alt A or Cmd-Opt A on a Mac. You'll have your choice of planes. Flying is another matter altogether, but the place to get started if you lack a joystick is the Google Earth keyboard controls help page.
If you open a YouTube video, click in the frame right after the video starts loading, then immediately type one of the keyboard's arrow keys, you can start playing a game of snakey on the video as it plays. Don't run into the walls!
Google gravity search
The Google Gravity chrome experiment by Mr. Doob is amusing--especially since the search page still works, with new search results piling up.
Google ASCII art search
ASCII art is imagery made of monospaced letters named after the storied character encoding scheme. Search for ASCII art on Google and you get a fittingly adapted Google logo.
Google Maps' pegman in Legoland
Google Maps' pegman character, used to signify the perspective of the street view feature, changes on special occasions. And when he shows up at Legoland in Carlsbad, Calif., he turns into a Lego character.
Google blue moon search
How often does the world experience a blue moon? Google Calculator results in Google search knows and will tell you.
Self-reference is just the sort of mathematical amusement that entertains Google nerds. Searching for "recursion" suggests that perhaps you meant to search for "recursion."
This isn't a Google Easter egg, and maybe isn't even an Easter egg at all. Instead it's with the sarcasm-laden Let Me Google That For You site, which people can use when others ask them silly questions easily answered with a search engine. This particular cached LMGTFY page, though, sets things off in an unending loop of reloading.