ok, I am not sure if this works on "anything" but should work on most things, like text, images, banners, links, image links. First, add this to your page where you want it to appear:
<SCRIPT LANGUAGE="Javascript"><!--
// stuarts random script
// for the source, visit http://www.lissaexplains.com/forum/showthread.php?p=416598#post416598

function random() {
};

random = new random();
number = 0;

// randomArray
random[number++] = "1"
random[number++] = "2"
random[number++] = "3"
random[number++] = "4"
random[number++] = "5"

increment = Math.floor(Math.random() * number);

document.write(random[increment]);

//--></SCRIPT>
Now, if you put that on a website, it would show a random number out of 1, 2, 3, 4 and 5. You can edit this by typing whatever you want to show if it lands on that in the middle of the " 's. You can have as many as you like, just delete or add another
random[number++] = "?"