<script type="text/javascript" src="~/Style/js/jquery.backstretch.min.js"></script>
<script type='text/javascript'>
var images = [
"http://dl.dropbox.com/u/515046/www/outside.jpg",
"http://dl.dropbox.com/u/515046/www/garfield-interior.jpg",
"http://dl.dropbox.com/u/515046/www/cheers.jpg"
];
$.backstretch("images[Math.floor(Math.random() * images.length)] + ')");
</script>