Moved to scripts + 3rd party apps. Next time post in the right section.
You could always use a http://meebo.com widget or http://chattango.com
I was looking to code it my self
its not a problem, that site seems very useful. thank youWhoops. Its http://chatango.com >< Sorry about that.
You should probably try to avoid coding it yourself unless you are a really experienced programmer because you are likely to leave some security holes which people could exploit, here are some tutorials anyway.
http://www.ajax-tutorials.com/tutorial-list/resource/Web_2_0_AJAX_Powered_ShoutBox/
http://ajax-tutorials.com/tutorial-list/resource/Ajax_PHP_Shoutbox_Tutorial/
AJAX is basically Javascript, hence Autnoimous Javascript A X something something. Anyways you don't need a program to make/use the shoutbox, just good ol Notepad (or a webmaking code design program of your choice)