// JavaScript Document
<!-- Begin 
var xPos = 20; 

var yPos = document.body.clientHeight; 

var step = 1; 

var delay = 30; 

var height = 0; 

var Hoffset = 0; 

var Woffset = 0; 

var yon = 0; 

var xon = 0; 

var pause = true; 

var interval; 

img.style.top = yPos; 

function changePos() { 

width = document.body.clientWidth; 

height = document.body.clientHeight; 

Hoffset = img.offsetHeight; 

Woffset = img.offsetWidth; 

img.style.left = xPos + document.body.scrollLeft; 

img.style.top = yPos + document.body.scrollTop; 

if (yon) { 

yPos = yPos + step; 

} 

else { 

yPos = yPos - step; 

} 

if (yPos < 0) { 

yon = 1; 

yPos = 0; 

} 

if (yPos >= (height - Hoffset)) { 

yon = 0; 

yPos = (height - Hoffset); 

} 

if (xon) { 

xPos = xPos + step; 

} 

else { 

xPos = xPos - step; 

} 

if (xPos < 0) { 

xon = 1; 

xPos = 0; 

} 

if (xPos >= (width - Woffset)) { 

xon = 0; 

xPos = (width - Woffset); 

} 

} 

function start() { 

img.visibility = "visible"; 

interval = setInterval('changePos()', delay); 

} 

start(); 

// End -->