Tamriel Rebuilt has an IRC channel where developers, members, and the public can hang out, chat, and ask questions. If you don't want to go through the hassle of choosing a client and getting everything set up, you can click here to join the chatroom. Just enter a nickname, press the big green start button, and you're connected! People who end up frequenting the chatroom might want some way to protect their nickname. For that, Chatspike has Nickserv. In short, it lets you protect your username with a password.
For you advanced users with your own preferred clients, the channel information is listed below:
Server: irc.chatspike.net
Channel: #tamriel
Port: 6667
In case the server catches fire or some other disaster happens, our backup channel can be found here:
Server: irc.lolibot.net
Channel: #tamriel
Port: 6667
If this talk of dedicated clients sounds interesting to you, you can find links to a few below: