I started using the old confbot python conference script in 2005 for my family. This essentially implements an IRC like conference room over Google Talk (or any Jabber/XMPP server). It has significantly increased family communication, and has become rather indispensable due to this.
Recently it's begun to have severe problems (people can't see each other in the conference room) which has nearly killed the usefulness of it.
Before I develop my own software or debug confbot (probably not - it uses an older jabber library that hasn't been updated since 2003) I wanted to see what other solutions exist that meet our needs:
Supports Google Talk (Sorry, I'm not going to try to convince everyone involved to move to a new IM or other client)
Free and open source (ideal, but not required)
Runs on Windows (Not a web service run by someone else)
Implements basic functionality such as kick/ban, emotes
Remembers who joined the conference room across restarts
Obeys Do Not Disturb and Busy status
Archives all activity
-Adam