function ChangeDiv(divId,divName,zDivCount) 
{ 
   
 for(i=0;i<=zDivCount;i++)
 {
     document.getElementById(divName+i).style.display="none";
  
 }
 document.getElementById(divName+divId).style.display="";
} 


lastScrollY = 0; 
function heartBeat(){  
var diffY; 
if (document.documentElement && document.documentElement.scrollTop) 
 diffY = document.documentElement.scrollTop; 
else if (document.body) 
 diffY = document.body.scrollTop 
else 
    {/*Netscape stuff*/} 
  
//alert(diffY); 
percent=.1*(diffY-lastScrollY);  
if(percent>0)percent=Math.ceil(percent);  
else percent=Math.floor(percent);  
document.getElementById("leftDiv").style.top = parseInt(document.getElementById("leftDiv").style.top)+percent+"px"; 


lastScrollY=lastScrollY+percent;  
//alert(lastScrollY); 
} 


window.setInterval("heartBeat()",1);