var lastScrollY = 60;
        var shopping_cart=document.getElementById("shopping_cart");
        function floatRefresh() {
				if (window.innerHeight) {
					diffY = window.pageYOffset
				}
				else if (document.documentElement && document.documentElement.scrollTop) {
					diffY = document.documentElement.scrollTop
				}
				else if (document.body) {
					diffY = document.body.scrollTop;
				}
                percent =.1*(diffY-lastScrollY);
                if(percent>0){
                        percent = Math.ceil(percent);
                }else{
                        percent = Math.floor(percent);
                }
				if(shopping_cart.style.pixelTop){
					shopping_cart.style.top = shopping_cart.style.pixelTop + percent +"px";				
				}else{
                shopping_cart.style.top = shopping_cart.offsetTop + percent+"px";
				}
                lastScrollY = lastScrollY + percent;
        }
        window.setInterval("floatRefresh()",10);