var imgPool;
var _currentImage = 0;
document.observe("dom:loaded", function() {
    imgPool = new Array();
    $$('a.img').each( function (item) {
     imgPool.push(item);
    });

    new PeriodicalExecuter( function (pe) {
        if( _currentImage < imgPool.length ) {
            new Effect.Fade( imgPool[_currentImage] , {duration:2, from:1, to:0});
            _currentImage ++;
        }
        if( _currentImage >= imgPool.length ) {
            _currentImage = 0;
        }
        $(imgPool[_currentImage]).setOpacity(0.0);
        imgPool[_currentImage].style.display = "block";
        new Effect.Fade(imgPool[_currentImage], {duration:2, from:0, to:1});
    }, 5);
});