<!-- Begin     
var xPos = 20;     
var yPos = document.body.clientHeight;     
var step = 1;     
var delay = 20;      
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 -->