var cache = [];
(function($) {

  // Arguments are image paths relative to the current page.
  $.preLoadImages = function(ar) {                    
	
	if(cache.length > 50) cache = []; //no memory leak
    
 	var args_len = ar.length;
    for (var i = args_len; i--;) {
	  var cacheImage = document.createElement('img');
      cacheImage.src = ar[i];
      cache.push(cacheImage);
	  
    }
  }
})(jQuery)