What is this wizardry? Just the magical world of computer science!

Mario - Super Mario Bros.

The Tetris Printer is a computer program that turns images into 8-bit art. Created by Meat Fighter, the program uploads an image to "print," then generates the correct colors by playing the game to leave behind specific blocks.

Click through here for an in-depth breakdown of how this occurs (warning: math) and a download of the Java 7 source code to start making your own creations.