// JavaScript Document

var delta=0.2;
var rightad=document.getElementById("rightad");

function topleft() 
{ 
window.setInterval("play()",50); 
} 

function play(){
 if(rightad.offsetTop!=(document.documentElement.scrollTop+500)) {
  var dy=(document.documentElement.scrollTop+500-rightad.offsetTop)*delta;
  dy=(dy>0?1:-1)*Math.ceil(Math.abs(dy));
  rightad.style.top=rightad.offsetTop+dy+"px";
 }
}


topleft();