Scroll_Y = -210;
function floatcenter()
{
    diffY = document.body.scrollTop;
    if(diffY != Scroll_Y)
    {
        percent = .1 * (diffY - Scroll_Y);
        if(percent > 0)
        {
            percent = Math.ceil(percent);
        }   
        else
        {
            percent = Math.floor(percent);
        }
        document.getElementById("float").style.pixelTop += percent;
        Scroll_Y = Scroll_Y + percent;
    }
}
window.setInterval("floatcenter()",1);