I just ran into a little issue while fooling around with rails and backbone.js. I wanted to start using haml_coffee_assets for templates and added the directory app/assets/templates. When refreshing the page to try and get ahold of the template I was getting an error Sprockets::FileOutsidePaths. Turns out I needed to restart WEBrick in order for the assets path to be "reloaded"
Just a quick gotcha!