simple slideshow with script.aculo.us derived from http://www.andrewsellick.com/30/simple-javascript-slide-show-using-scriptaculous

simple-slide-show.css

#slide-images {
  position: relative;
  display: block;
  margin: 0px;
  padding: 0px;
  width: 738px;
  height: 234px
  overflow: hidden;
}

#slide-images li {
  position: absolute;
  display: block;
  list-style-type: none;
  margin: 0px;
  padding: 0px;
}

#slide-images li img {
  display: block;
}

simple-slide-show.js

var delay = 4000;
var start_frame = 0;

function start_slideshow(delay) {
  setTimeout(fadeInOut(delay), delay);
}

function fadeInOut(delay) {
  return(function() {
    lis = $$('#slide-images>li');
    new Effect.Appear(lis[1], { duration: 2, afterFinish: function(obj) {
      lisFade = lis[0].remove();
      lisFade.hide();
      $('slide-images').appendChild(lisFade);
      start_slideshow(delay);
    }});
  })
}

Event.observe(document, 'dom:loaded', function() {
  var lis = $$('#slide-images>li');
  if(lis.length > 1) for(i = 1; i < lis.length; i++) lis[i].hide();
});

Event.observe(window, 'load', function() {
  if($$('#slide-images>li').length > 1) start_slideshow(delay);
});