Try it by pressing Up Up Down Down Left Right Left Right B A Start (Enter). Plurk also implemented the Konami Code.

Plurk Konami Code Up Up Down Down Left Right Left Right B A Start
You would see your time line start waving up and down.
Try it by pressing Up Up Down Down Left Right Left Right B A Start (Enter). Plurk also implemented the Konami Code.

Plurk Konami Code Up Up Down Down Left Right Left Right B A Start
You would see your time line start waving up and down.
Facebook also added Konami Code where it adds some lens flare effect on your pages:

Facebook Konami Code Up Up Down Down Left Right Left Right B A Start
You can try pressing Up Up Down Down Left Right Left Right B A Start. [via Techcrunch]
Ask Google the number of horns on a unicorn.

(Ask google the number of horns on a unicorn.)
Google knows the answer.
Want to know the story behind Up Up Down Down Left Right Left Right B A Start? It’s sometimes referred to as Konami code and is implemented in many games, even those not from Konami.
Up, Up, Down, Down, Left, Right, Left, Right, B, A
First executed on an NES game (not Contra!) developed by Konami in 1986, the Konami code (and slight variances of it) can now be inputted in more than 125 different computer, video, and arcade games—some of which aren’t even developed by Konami, the company that created the code in the first place!
Because Contra was one of the more popular NES titles in the day and basically required the Konami code for the average player to complete (the code granted 30 lives from the start, instead of three), most people associate the code’s existence with it. In reality though, the Konami code first appeared in Gradius in 1986, two years before Contra.
In Metal Gear Solid 2: Sons of Liberty on PS2, entering the sequence at the end of the game has the main character, Snake, barking, “STOP FOOLIN’ AROUND KID!” At the end of Metal Gear Solid 3: Snake Eater for PS2, Snake confirms “One More to Go…” referring to the fourth and final installment in the series on PS3.
There are a number more of hilarious consequences for using the code, like it causing your main character to self destruct in Contra 4 if you use the code more than once per level to power-up your guns or in the Dog-developed NES title 3-D World Runner, a message pops up that exclaims, “I AM NOT KONAMI.” The code can even be used in Google Reader of all things, enabling a different background color for the left-hand navigation and updating all unread counts to 30 (a homage, no doubt, to Contra’s 30 lives). You know the code has reached pop culture when Google starts using it. (Source: Game Informer)
There you have it, this is what happen in Google Reader, you get a ninja and your unread count becomes 30. Refreshing will return your unread count to the original value. Pretty cool I say.

(Press Up Up Down Down Left Right Left Right B A in Google Reader and get Ninja!)
The code is even in a song by The Moldy Peaches – Anyone Else But You (of Juno fame).
Now with Python, you can do an import antigravity.
And soon you’ll be flying.

(From XKCD)
webbrowser.open("http://xkcd.com/353/")
(Source: Python)
XKCD comics have been receiving quite a bit of attention recently hasn’t it?
Well, type ‘about:robots’ without quotes in the location bar in Firefox 3.

(Source: LaughingSquid)
You can of course press the button.