ET does not have a chat room, but there is a chat room on the DALnet Internet Relay Chat network. It runs every Friday at 9pm, although no one has been in there for months. It used to run every Sunday at 9pm as well, but I'm not sure if it still does. Everyone gathers in a channel called #Titanic.
Click on this link MIRC to download software for the PC, or this link IRCLE for the Mac. They are free to download, but there is a one month trial period, so it's recommended that you register it if you plan to use it after that.
The chat is a lot of fun and I've met some great people in there.