Sandy Noble created his “Polargraph” machine, which uses simple machines and regular pens to great drawings, utilizing a polar coordinae system (as opposed to the normal graph “cartesian” system that most people are familiar with).

Quote from the project website:

“The whole system is fairly technologically agnostic, but the current incarnation uses an Arduino microcontroller and an Adafruit Motorshield, along with a couple of stepper motors. The application that dri ves it from the computer is written in Processing. It decodes a bitmap and creates a map of the file using a polar coordinates system, recording pixel position, size and brightness. The hardware requests each pixel in turn, and renders it on the page using it’s own shading and movement algorithms.”