Advanced javascript tutorial

http://ejohn.org/apps/learn/ – A really good advanced javascript tutorial.
If you want to be able to understand the code below, than this tutorial is the right thing.

// The .bind method from Prototype.js
Function.prototype.bind = function(){
  var fn = this, 
  args = Array.prototype.slice.call(arguments),
  object = args.shift();
  return function(){
    return fn.apply(object,
      args.concat(Array.prototype.slice.call(arguments)));
  };
};