Looking for code to show online - offline availability.

[dunkin]

Hello gang,
I am looking for some coding, probably done with php, that will show when someone is on line, off line or busy. It would work similar to what yahoo provides. When you are logged into yahoo, the icon next to your name is lit showing you are online and unlit when you are off line.

You would need to log in with a username and password and show that you are available, unavailable or busy.

I know of an example of this, but would prefer to correspond the site via email. If anyone can help, I would really appreciate it. Please contact me at webmaster@dunkinsworld.com
Again, thanks
Dunkin