One of the site's many features is giving you the ability to turn text into an image. I downloaded the preface to my latest book The Day We Found the Universe, for example, and chose to display it as a "wordle," which shows how frequently words appear in your text by the size of each word. You can even tweak these word "clouds" with different fonts, layouts, and color schemes. Here's how mine came out:
It's fascinating how well the central themes of my book just pop out, as if by magic. Edwin Hubble would certainly have liked the outcome.