var  lastScrollY = 0 ; // 滚动条距顶部位置
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 */ }
    
    percent = . 1 * (diffY - lastScrollY); 
     if (percent > 0 )percent = Math.ceil(percent); 
     else  percent = Math.floor(percent); 
    document.getElementById( " gvRightAd " ).style.top = parseInt(document.getElementById( " gvRightAd " ).style.top) + percent + " px " ;

lastScrollY = lastScrollY + percent; 
}
window.setInterval( " heartBeat() " , 100 ); // 每0.1秒钟执行一次

<! DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" >
< html  xmlns ="http://www.w3.org/1999/xhtml"   >
< head >
     < title > 最简单明了的QQ在线客服代码 </ title >
     < script  type ="text/javascript"  src ="style/floatAd.js" ></ script >
</ head >
< body  style ="height:1000px;" >
< div  id ="gvRightAd"   style ='right:50px;POSITION:absolute;TOP:230px;text-align:center;width:117px;' >
     < table  style ="width:117px;"  cellpadding ="0"  cellspacing ="0" >
         < tr >
             < td >< img  src ="images/qq/qqbg1.gif"  alt =""   /></ td >
         </ tr >
         < tr >
             < td  style ="background:url(images/qq/qqbg2.gif) repeat-y;" >
                 < div > <!-- 这里的QQ代码请到http://imis.qq.com/webpresence/code.shtml申请 -->
                 < a  href ="http://sighttp.qq.com/cgi-bin/check?sigkey=7cd7c4f0fe8acae47af475bfd5864dd2a9910c5e16692240f96d1d9343fa6e82b8685b01340a0c99b5f625bc523faf6d34ae463cf21aba0e" ; target =_blank;  onclick ="var tempSrc='http://sighttp.qq.com/wpa.js?rantime='+Math.random()+'&sigkey=7cd7c4f0fe8acae47af475bfd5864dd2a9910c5e16692240f96d1d9343fa6e82b8685b01340a0c99b5f625bc523faf6d34ae463cf21aba0e';var oldscript=document.getElementById('testJs');var newscript=document.createElement('script');newscript.setAttribute('type','text/javascript'); newscript.setAttribute('id', 'testJs');newscript.setAttribute('src',tempSrc);if(oldscript == null){document.body.appendChild(newscript);}else{oldscript.parentNode.replaceChild(newscript, oldscript);}return false;" >< img  border ="0"  SRC ='http://wpa.qq.com/pa?p=1:1090126549:1'  alt ="张老师" ></ a >
                 </ div >
                 < div >< a  href ="http://sighttp.qq.com/cgi-bin/check?sigkey=7cd7c4f0fe8acae4d6822fba4ae9ad0363e4805f0a646f849ad95f6a69ffc6c52caf5f5505cbbaa4d5666e4f402e1f9177da136fadfad826" ; target =_blank;  onclick ="var tempSrc='http://sighttp.qq.com/wpa.js?rantime='+Math.random()+'&sigkey=7cd7c4f0fe8acae4d6822fba4ae9ad0363e4805f0a646f849ad95f6a69ffc6c52caf5f5505cbbaa4d5666e4f402e1f9177da136fadfad826';var oldscript=document.getElementById('testJs');var newscript=document.createElement('script');newscript.setAttribute('type','text/javascript'); newscript.setAttribute('id', 'testJs');newscript.setAttribute('src',tempSrc);if(oldscript == null){document.body.appendChild(newscript);}else{oldscript.parentNode.replaceChild(newscript, oldscript);}return false;" >< img  border ="0"  SRC ='http://wpa.qq.com/pa?p=1:1131441761:1'  alt ="王老师" ></ a >
                 </ div >
             </ td >
         </ tr >
         < tr >
             < td >< img  src ="images/qq/qqbg3.gif"  alt =""   /></ td >
         </ tr >
     </ table >
        
     </ div >
</ body >
</ html >