<span id="spnTime"></span><script language="javascript">
var http = new XMLHttpRequest;
http.open(
"HEAD""."false);
http.send(
null);
var curDate = new Date;
var offsetTime = curDate - Date.parse(http.getResponseHeader("Date"));
setInterval(
function()
{
    curDate.setTime(
new Date - offsetTime);
    document.getElementById(
"spnTime").innerHTML = curDate.toLocaleString();
}
1000);
</script>