I don't know how it works exactly, but it looks like SE chat rooms can hold scheduled events. For example, Science Fiction & Fantasy has a recurring event for book recommendation.
As an SE site about Japanese language & usage, how can we take advantage of this feature? What are some fun and/or useful event themes?
Update: How scheduled event works:
I couldn't find any official help document about it, but it looks like room owners can create a scheduled event from the 'schedule' tab of a room's info page.
And then, other users can sign up ("register" in the screenshot below) to let everyone know s/he's coming.
I guess that's the extent of the built-in functionality for scheduled events; when the time comes, we're on our own to gather and do whatever the event is about. Later, anyone can manually bookmark the conversation for posterity's sake (Science Fiction & Fantasy's room has examples of such bookmarked conversations here).