JavaScript Namespace Generator - Create namespaces on the fly using dot delimiters (accessible via dot notation).

gistfile1.js

var Namespace = (function (global) {
	"use strict";
	
	// empty object to verify namespaced objects
	function Namespace() {}
	
	return function (namespace) {
		var chunks = namespace.split('.'),
			lastObjRef = global,
			i;
			
		// iterate over chunks
		for (i = 0; i < chunks.length; ++i) {
			if (typeof lastObjRef[chunks[i]] !== 'undefined') {
				if (lastObjRef[chunks[i]] instanceof Namespace === true) {
					lastObjRef = lastObjRef[chunks[i]];
					// next iteration
					continue;
				} else {
					throw new Error("Non Namespace Object exists, cannot create namespace.");
				}
			}
			
			// create new object
			lastObjRef[chunks[i]] = new Namespace();
			
			// assign new last object reference
			lastObjRef = lastObjRef[chunks[i]];
		}
		
		// return reference to prevent double typing
		return lastObjRef;
	};
	
}(this));

Example usage:
Namespace('hello.world').Class = function () {alert('test');}
hello.world.Class();