Eric Miraglia explains Douglas Crockford's Module pattern, a way of creating encapsulated JavaScript functions that offer private and public methods and properties. It uses an anonymous function that returns an object containing our methods, and avoids the big issue of cluttering up the global namespace with global functions. Its based on the Singleton pattern.
Tim Huegdon and Mark Aidan Thomas create an elegant wrapper to the YUI Connection Manager that manages repeating Ajax JSON requests. Tim describes the use of Custom Events, and the use of the Observer design pattern, dissects the code and offers a tidy demonstration of the working code. This simplifies JSON requests into declaring a simple function to process the returned JSON object, and a single line to fire off the request (within a setInterval if required)