google has something called google talk gadget which allows your visitors to use google talk at your page.. You can ask them to add your google talk ID and chat with you.
If you want to have a real chatroom, make an IRC channel somewhere, and let people who haven't got an IRC client to connect using pjIRC or similar. If you just want something that you can say stuff on, Lace looks interesting. Or you can go with a simple shoutbox script (these things are everywhere).
I "work" for a place called CentralChat - You can host a channel on a IRC server (Free) and CentralChat gives you a Java applet for your site, check it out here: http://www.centralchat.net/webmasters/ (Useful, so you don't need to waste SQL and other resources just to chat.)
does anyone know of a "free" chat software that you can use on your site where it connects to your mysql database directly? i know that you can't really expect too much from free software. i'm just wondering maybe some of you know of some software that i can use.
I advise the use of http://gtchat.de/news_en.xhtml when possible. If it is not then I would say use some form of php/java chat. FlashChat or any Flash run chat room is incredibly easy to "hack"/expoit.