Although the two chat-event-related meta questions (1) (2) have not yet received very many answers, the chat room itself has been chock full of topic suggestions recently. It's a gold mine! I think we should save all those great suggestions as meta answers here.
Let's hear your suggestions for chat event topics. One topic per answer, please!
The votes would decide what the next topic should be: we'll just pick the topics in descending order of their votes. Popular topics can be re-run at intervals.
We can "tick off" the topics as we cover them, and then also edit the suggestions to include links to the chat transcript, include a summary, and additional links.