The Mixin Pattern

http://addyosmani.com/resources/essentialjsdesignpatterns/book/#mixinpatternjavascript

/* Car Class */
var Car = function(settings){
	this.model = settings.model || 'no model provided';
	this.colour = settings.colour || 'no colour provided';
};

/* Mixin Class */
var Mixin = function(){};
Mixin.prototype = {
	driveForward: function(){
		console.log('drive forward');
	},
	driveBackward: function(){
		console.log('drive backward');
	}
};


/* Augment existing class with a method from another class */
function augment(receivingClass, givingClass) {
	/* only provide certain methods */
	if (arguments[2]) {
		for (var i=2, len=arguments.length; i