<html>
<head>
<script type="text/javascript" language="javascript">
window.onload = function() {
var a=Math.round(Math.random()*3)
var images = [];
images[0] = 'http://javascript.ru/forum/images/smilies/smile.gif';
images[1] = 'http://javascript.ru/forum/images/smilies/laugh.gif';
images[2] = 'http://javascript.ru/forum/images/smilies/stop.gif';
images[3] = 'http://javascript.ru/forum/images/smilies/yes4.gif';
var ccr = images[a];
document.getElementById("pica").style.background = "url("+ccr+")";
}
</script>
<style>
#pica {width: 100px;height: 100px;}
</style>
</head>
<body>
<div id="pica"></div>
</body>
</html>