Short Screencasts of Gourmet Ruby, by Avdi Grimm
Guides to the core and standard libraries, as well as selected Rubygems.
How to use Hash#fetch to provide defaults for missing keys, and why you might prefer that to other techniques for defaulting values.
Hash#fetch is one of my favorite methods. In this episode, I take a look at using it to assert the existence of hash keys.
A short introduction to using Ruby's Forwardable library for object composition.