I sometimes read where people on this board talk to each other in chat. Is there some kind of chat service associated with this board? Or is it an IRC channel? What’s up with that?
Standard disclaimer: The chat room is no way affiliated with The Straight Dope, The Straight Dope Message Board, or The Chicago Reader.
It’s an IRC channel. Type in #straightdope.
Then I guess I’ll have to download an IRC client.
I guess you will. 
The IRC chat can also be accessed via undernets webchat client at http://www.undernet.orp/webchat.php
Logon and then type /join #straightdope
The chat room is only on Undernet servers, so if you use an IRC client you will need to log on to one of these.
Standard disclaimer: The chat room is no way affiliated with The Straight Dope, The Straight Dope Message Board, or The Chicago Reader.
The correct url is http://www.undernet.org/webchat.php.