function slideSwitch() {
    var $active = $('#slideshow DIV.active');
    if ($active.length == 0) $active = $('#slideshow DIV:last');

    var $next =  $active.next().length ? $active.next() : $('#slideshow DIV:first');
    // ramdom
    // var $sibs = $active.siblings();
    // var rndNum = Math.floor(Math.random() * $sibs.length);
    // var $next = $($sibs[rndNum]);
    // -----------
    $active.addClass('last-active');
    $next.css({ opacity: 0.0 })
        .addClass('active')
        .animate({ opacity: 1.0 }, 1500, function() {
            $active.removeClass('active last-active');
        });
}