@Chen:
of course it's very easy if you have a static ip, but not all of us have, and the cookie part is important for me
@Bob: you can change the link in admin/index.php to tell you the actual info as well, but as the ACP is based on frames, that won't help you once you've toggled the debug madoe, that's why the neutral way was choosen by me
if the debug mode is enabled is easy to see on your forum's footer