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Michael Calkins has a whole free, public series called Getting Started with AngularJS on YouTube. It's pretty neat for us to see, since the entire series uses CodePen to demonstrate the concepts. We of course support Angular.
Here's the overview video:
Not only is CodePen a perfect place for screencasting because of the single-screen code-and-demo-together but-still-customizable approach, but also because then the demos you make are available publicly for anyone to play with and use.
Michael has lots of fun Angular demos on CodePen. Here's an interactive music player in about 100 lines of code!