9. Minecraft's Ghost - Herobrine
From one massive world to the king of the freeform expanse itself, Minecraft - and the idea that even when playing offline you're not the only one constructing things in your game world. 'Herobrine' is the name given to what appears to be a mirror of the main character's avatar, as players started reporting houses and other structures appearing in their games even though they'd not built them themselves. What's freakier (if you're into this sort of thing) is the idea bandied about that Herobrine is the digital ghost of Minecraft creator Markus Persson's brother, hence why he looks the same as you albeit with large, hollowed-out white eyes. Okay, bubble-bursting time; Notch doesn't have a brother... OR DOES HE?! Spoilers: No, he doesn't.