This 2009 "subway map" of the Internet is based on Tokyo's subway system. This design company (like a few others, I think) does one of these every year. It's a articular genre of a thing called an "infographic" that you see everywhere.
A ally interesting article about a former NSA contractor who has developed 4 different types of fonts so that they cant be read by Optical Character Recognition programs. The video does a nice job of showing how it works.