text javascript mensaje animado

Código Javascript

<!-- PRIMER PASO: Copiar dentro del tag HEAD -->
<style type="text/css">
#supertext {
position:absolute;
left:0;
top:0;
visibility:hide;
visibility:hidden;
}
</style>
<!-- SEGUNDO PASO: Copiar dentro del tag BODY -->
<script type="text/javascript">

// Script Original: Lloyd Hassell's
// Mensaje
var thecontent='<h2><font color="#0000FF">Depósito de JavaScripts!</font></h2>'
// Tiempo de animación en milisegundos ('' = infinito)
var hidetimer=7000;
// Velocidad
var BallSpeed = 10;

var contentWidth;
var contentHeight;
var maxBallSpeed = 50;

var xMax;
var yMax;
var xPos = 0;
var yPos = 0;
var xDir = 'right';
var yDir = 'down';
var superballRunning = true;
var tempBallSpeed;
var currentBallSrc;
var newXDir;
var newYDir;
function initializeBall() {
   if (document.all) {
      xMax = document.body.clientWidth
      yMax = document.body.clientHeight
      document.all("supertext").style.visibility = "visible";
      contentWidth=supertext.offsetWidth
      contentHeight=supertext.offsetHeight
      }
   else if (document.layers) {
      xMax = window.innerWidth;
      yMax = window.innerHeight;
      contentWidth=document.supertext.document.width
      contentHeight=document.supertext.document.height
      document.layers["supertext"].visibility = "show";
      }
   setTimeout('moveBall()',400);
   if (hidetimer!='')
   setTimeout("hidetext()",hidetimer)
   }
function moveBall() {
   if (superballRunning == true) {
      calculatePosition();
      if (document.all) {
         document.all("supertext").style.left = xPos + document.body.scrollLeft;
         document.all("supertext").style.top = yPos + document.body.scrollTop;
         }
      else if (document.layers) {
         document.layers["supertext"].left = xPos + pageXOffset;
         document.layers["supertext"].top = yPos + pageYOffset;
         }
      animatetext=setTimeout('moveBall()',20);
      }
   }
function calculatePosition() {
   if (xDir == "right") {
      if (xPos > (xMax - contentWidth - BallSpeed)) { 
         xDir = "left";
         }
      }
   else if (xDir == "left") {
      if (xPos < (0 + BallSpeed)) {
         xDir = "right";
         }
      }
   if (yDir == "down") {
      if (yPos > (yMax - contentHeight - BallSpeed)) {
         yDir = "up";
         }
      }
   else if (yDir == "up") {
      if (yPos < (0 + BallSpeed)) {
         yDir = "down";
         }
      }
   if (xDir == "right") {
      xPos = xPos + BallSpeed;
      }
   else if (xDir == "left") {
      xPos = xPos - BallSpeed;
      }
   else {
      xPos = xPos;
      }
   if (yDir == "down") {
      yPos = yPos + BallSpeed;
      }
   else if (yDir == "up") {
      yPos = yPos - BallSpeed;
      }
   else {
      yPos = yPos;
      }
   }
function hidetext(){
if (document.all)
supertext.style.visibility="hidden"
else if (document.layers)
document.supertext.visibility="hide"
clearTimeout(animatetext)
}
if (document.all||document.layers){
document.write('<span id="supertext"><nobr>'+thecontent+'</nobr></span>')
window.onload = initializeBall;
window.onresize = new Function("window.location.reload()");
}
</script>