Press F11 to go fullscreen & select:

"Hack" like a programmer in movies and games!
  WATCH THE VIDEO You can exit fullscreen by pressing .
Simply randomly mash your keyboard and code will display on your screen.
Press / * - + 2 0 on your numpad to activate various effects, or ESC to remove them

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[FEEDBACK] This site is intended to be a practical JOKE. The "hacking" isn't real, and
everything you type isn't stored anywhere. Thx to Lexuzieel for his help. Script by Simone Masiero.