<script language="
javascript" src="jquery1.3.2.js"></script>  
<script language="javascript">  
jQuery(function($){  
    var url = 'http://chaxun.1616.net/s.php?type=ip&output=json&callback=?&_='+Math.random();    
    $.getJSON(url, function(data){  
        alert(data.Ip);    
    });  
});  
</script>