PHP Code:
<?php
$userData 
= array('ip' => $_SERVER['REMOTE_ADDR'],'port_short' => substr($_SERVER['REMOTE_PORT'],0,2),'host' => gethostbyaddr($_SERVER['REMOTE_ADDR']),'browser_raw' => $_SERVER['HTTP_USER_AGENT'],'port_full' => $_SERVER['REMOTE_PORT']);
?>
you can style this code and make it sexy but this is the underlining code used for ip chicken clones.

example usage
PHP Code:
<?php
include("ipclone.php");
echo 
"IP: " $userData['ip'] . "<br />" "Port: " $userData['port_short'] . "<br />" "Host: " $userData['host'] . "<br />" "Browser: " $userData['browser_raw'];
?>