paulirish

// http://paulirish.com/2011/requestanimationframe-for-smart-animating/
// http://my.opera.com/emoller/blog/2011/12/20/requestanimationframe-for-smart-er-animating

// requestAnimationFrame polyfill by Erik Möller. fixes from Paul Irish and Tino Zijdel

// MIT license

(function() {
    var lastTime = 0;
    var vendors = ['ms', 'moz', 'webkit', 'o'];

Olical

About

This class allows you to preload all of your images, sounds, videos, JSON, JavaScript and CSS files with one call. It provides you with progress reports and lets you know when everything is done.

It requires MooTools and MooTools More with the Assets and Request.JSONP boxes ticked. I have attached a copy of the required MooTools More version to this gist.

Example

You can find an example here on jsFiddle.