(function($) {

$.fn.randomize = function(childElem) {
  return this.each(function() {
      var $this = $(this);
      var elems = $this.children(childElem).get();
      
      elems.sort(function() { return (Math.round(Math.random())-0.5); });  

      $this.empty();  

      for(var i=0; i < elems.length; i++)
        $this.append(elems[i]);      

  });    
}
})(jQuery);