Simple fade slideshow by Jonathan Snook (http://snook.ca/archives/javascript/simplest-jquery-slideshow).

slide.html

<div class="fadein">
  <img src="http://farm3.static.flickr.com/2610/4148988872_990b6da667.jpg">
  <img src="http://farm3.static.flickr.com/2597/4121218611_040cd7b3f2.jpg">
  <img src="http://farm3.static.flickr.com/2531/4121218751_ac8bf49d5d.jpg">
</div>

slide.js

$.fn.slideShow = function(timeOut) {
  var $elem = this;
  this.children(':gt(0)').hide();
  setInterval(function() {
    $elem.children().eq(0).fadeOut().next().fadeIn().end().appendTo($elem);
  }, timeOut || 3000);
};

$(function() {
  $('.fadein').slideShow();
});