Besides form controls, alerts & similar simple JavaScript usage, you can almost do anything with the help of JavaScript (& Canvas). Some samples are: * Drag’n drops * Animations * CSS manipulations, Ajax & more.
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.
The hardest part about using drupal's javascript features is knowing where to begin: they remained an arcane mystery to me until today. After drinking a bit of whiskey, and studying how core was using Drupal.behavior, I learned it couldn't be simpler. If you don't know how to do this, take a moment:
Repository of utility libraries that can be used with the Google Maps JavaScript API v2.
