What kind of chat software are you using? If you are using chatspace it has a built in feature to grab the users in a specific chat room by calling a variable I.E. %USERS%. Otherwise I would perform a custom /who and count the different idents or rooms chatters are in and inc them accordingly. For instance you could type /who chatlinks in which case your custom /who script would count the users in chatlinks and display a total. Then you could sock write that to a file every so often. I have done this both ways and if you are using chatspace it is much easier. Yet not impossible the other way. Also, You could program a php bot to connect to the server and join the room, that would get an accurate count every time someone viewd the page. though it wouldn't have an automatic refresh without javascript or ajax or something similar. Good luck.