var xoff = 0; 
var yoff = 61; 
var inc = 1;
var date = new Date();
xoff = (date /60) % screen.width;
function move() {
xoff +=inc;
if (xoff>screen.width-20) {xoff=0;}
ball.top = yoff;
ball.left = xoff;
setTimeout("move()", 50);}