The Unofficial Ruby Usage Guide

You may be interested to know that this document was originally written for internal use in the Operations department at Google. At the time, I was campaigning for the right to use Ruby on internal projects and I felt that a style and usage guide would probably assist in the battle for the language’s acceptance, as the officially sanctioned languages at the time already had one. If nothing else, we’d at least all end up writing code that was easier to maintain.
(Link: The Unofficial Ruby Usage Guide)