function scrollTop(){
  if(window.pageYOffset) return window.pageYOffset;
  if(document.compatMode == "CSS1Compat") return document.body.parentNode.scrollTop;
  if(document.body.scrollTop) return document.body.scrollTop;
  return 0;
}
function scrollWin(){
  var pos = scrollTop();
  pos += (0-pos)*0.1;
  if(pos<=0) pos = 0;
  else setTimeout("scrollWin()",0)
  window.scrollTo(0,pos);
}
document.write('<p class="pagetop"><a href="javascript:scrollWin()">&Delta;Page Top</a></p>');