My first Goodie

There, a pull request, just as proposed at the end of the tutorial. I don't know if you guys merge those or not, but I figured I'd give it a try!
See the attached screen-shot for results.

![1416263487434570386](https://cloud.githubusercontent.com/assets/878305/5078105/df546af4-6ea9-11e4-8126-7b736364b3b5.png)