Do a barrel roll
Type in "do a barrel roll" and the search results page spins on its head.
You can also enter "zz" or "rr" to produce the same effect. This is a reference to Star Fox, a Nintendo game series where those button combos on the controller sent the titular pilot character's plane a-rolling.
For a similar yet less nauseating outcome, type in "askew." Search results turn aslant.
Flip a coin, roll a die
Today's day and age may find you with an arbitrary decision to make and nothing to flip but an iPhone. Don't do it! Google can flip a virtual coin, complete with a non-denominational coin animation and heads-or-tails results. Just search "flip a coin".
You can also enter "roll a die" and Google rolls out a random number from 1-6. It's probably not as readily applicable as flipping a coin, unless you know some good single-die games.
If you're desperate for a mobile game but just can't fit any more downloads, take advantage of Google's traditional games that can be played in the app or browser.
Try Googling "Solitaire" or "tic-tac-toe". For the latter, you can play with a friend or versus a bot at various levels of difficulty.
The gaming term "Zerg Rush" is named for a specific game – StarCraft – but it's a familiar trope. It refers to an instance where you're mobbed by a mass quantity of weak opponents that are easy enough to kill on their own, yet threaten to snuff you out with sheer volume.
Google "Zerg Rush" and once you hit the results page, you'll need to click the flying "o" characters before they destroy your search results. The counter in the top right corner keeps track of how well you do.
Atari Breakout is a classic single-player paddle game. It's easy to play and even easier to access through Google, complete with retro bleep and blip sound effects.
Perform a Google image search (type in the search box on Google.com and then click "Images" when you get to the results, or search directly from images.google.com) for "Atari breakout." The images rearrange into a grid of blocks for you to destroy by deflecting a ball against them with your paddle.
Search "Pac-Man" and you'll score the opportunity to revisit a favorite homepage doodle from May 21, 2010, the 30th anniversary of this arcade classic's release. It's a full version of the game that you can play with arrow keys on a desktop or by swiping the screen on mobile.
Super Mario Bros.
Remember the gratifying thrill of finding a coin block in the original Super Mario Bros. NES game? Google "Super Mario Bros" and look to the right sidebar, where there's a flashing Mario block with your name on it. However many times you click it, they'll be the most satisfying clicks you've had in a long time.
Google in 1998
Even if you think you remember what the internet was like back in the day, you might be surprised by just how sparse it looks. Search "Google in 1998" and see how the results would have looked pre-Y2K (remember that?).
Horrible html tags are another relic from the web's early days. Type "blink html" into the search bar and see for yourself just how awful the internet used to be. Google applies the original blink effect to every instance of "blink" and "html" in the search results.
A tribute to Three Dog Night
Enter "the loneliest number" in the search bar. A calculator is displayed over the top result. Its autofilled value? One.
It's not just Google dropping a sad truth bomb. It's also a cheeky reference to the song "One", a 1969 Top-5 hit on the U.S. Billboard charts for folk-rock band Three Dog Night. The song is a bit of an ear worm; apologies if it's stuck in your head the rest of the day.
This Easter egg invokes the concept of "six degrees of separation", the idea that we live in an ever-shrinking world and that no one is more than six degrees of separation apart. The spinoff idea "six degrees of Kevin Bacon" asserts that no celebrity is more than six co-stars away from the prolific Mr. Bacon.
Type in any actor's name followed by "Bacon number" into the search box. Google will tell you their degrees of separation. Good luck finding a major film actor more than 3 or 4 degrees away – I typed in a dozen names off the cuff and couldn't get a Bacon number higher than two.