var preloaded = new Array();
function preload_images() {
    for (var i = 0; i < arguments.length; i++){
        preloaded[i] = document.createElement('img');
        preloaded[i].setAttribute('src',arguments[i]);
    };
};
preload_images(
    '/i/loading.gif',
    '/i/indicator.gif',
    '/i/menu/consulting-a.gif',
    '/i/menu/mistery-shopping-a.gif',
    '/i/menu/ratings-a.gif'
);