/* This was originally by Armin Ronacher on http://zine.pocoo.org/ */

function slideshow(expr, options) {
  options = options || {};
  var
    items = $('li', expr).hide(),
    index = -1,
    timeout = options.timeout || 4000,
    fadeTime = options.fadeTime || 'slow';

  if (!items.length)
    return;

  function nextImage() {
    if (index >= 0)
      $(items[index]).hide();
    $(items[index = (index + 1) % items.length]).show();
    window.setTimeout(nextImage, timeout);
  }
  nextImage();
}