Polybius is a supposed arcade game featured in an Internet urban legend. According to the story, the Tempest-style game was released to the public in 1981, and caused its players to go insane, causing them to suffer from intense stress and horrific nightmares. A short time after its release, it supposedly disappeared without a trace. No evidence for the existence of such a game has ever been discovered.
Nowadays you can find imitations that try to imitate the real one, sometimes it causes the same effect So , You dare play it ?
Here is a link: http://www.megaupload.com/?d=UU0DULCM
The secret code to activate the crazy effects is:
35 34 31 54 12 24 45 43
Use it at your own risk