div.fixedTop{
  position:fixed;
  _position:absolute;
  top:0;
  _top:expression(eval(document.body.scrollTop));
  margin:0;
  padding:0;
 }

div.fixedBottom{
  position:fixed;
  _position:absolute;
  bottom:0;
  _top:expression(document.body.scrollTop+document.body.clientHeight-this.clientHeight);
  margin:0;
  padding:0;
}

div.fixedMiddle   {               }
div.paddingTop    { height:270px; }
div.paddingBottom { height:40px;  }

body {
  background:url(foo) fixed; 
}