Directly view GitHub raw HTML/CSS/JS in Chrome
This Chrome Extension intercepts requests to js, css, and html files on raw.github.com and changes the default content-type from text/plain so that the browser will properly render them, rather than merely showing plain text.
Demo: After installing the extension to Chrome (load unpacked extension) try it out with the Backbone.js Todos example: https://raw.github.com/documentcloud/backbone/master/examples/todos/index.html