var mess = new Array('<img src="randf/bear.jpg" width="500" height="292" />','<img src="randf/skeleton.jpg" width="500" height="292" />','<img src="randf/banana.jpg" width="500" height="292" />','<img src="randf/tobin.jpg" width="500" height="292" />');
var max = mess.length;
var num = Math.floor((Math.random() * max));
document.writeln(mess[num]);