Shoutbox

No whatsmyip.com doesn't get it right, but sites such as http://www.grc.com 's "shieldsup" does.  Most forums get its wrong I find, but some get it right it varies from site to site.

The plugin does much the same as plus: it accesses a web page done in PHP and located at http://members.lycos.co.uk/itstom/ipplug/ip.php

Tis a PHP script don't know if that makes any difference, I think it just depends on the way of retrieving the IP with HTML or whatever, some methods are more accurate.