CasperJS is an open source navigation scripting & testing utility written in Javascript and based on PhantomJS — the scriptable headless WebKit engine. It eases the process of defining a full navigation scenario and provides useful high-level functions, methods & syntactic sugar for doing common tasks
Chosen is a javsacript plug-in that makes long, unwieldy select boxes much more user-friendly. It is currently available in both jQuery and Prototype flavors.
In-browser code editing made bearable
CoffeeScript is a little language that compiles into JavaScript. Think of it as JavaScript's less ostentatious kid brother — the same genes, roughly the same height, but a different sense of style. Apart from a handful of bonus goodies, statements in CoffeeScript correspond one-to-one with their equivalent in JavaScript, it's just another way of saying it.
