With a little math knowledge, you can make a simple calculator. We've seen calculators made from dominoes, but today's calculator is even simpler: It's drawn on a piece of paper. To add numbers, you just follow the tubes.

In the video below, comics artist Jason Shiga shows off his paper calculator. It's pretty simple—it can only do binary adding—but you can extrapolate how all calculators work based on this simple set of pathways. Enjoy:

Who knew calculators could be a series of tubes?