Question: What sessions would people like to have at the 2017 Barnraising?

Inspired by @cfastie's session-organizing post for LEAFFEST, which worked pretty well, I'd like to know what session ideas people have for the Barnraising on Nov 3-5. I've seen a couple on the wiki already (but I don't know who posted them):

I have a few ideas as well, and will post below. Chris's format asked that folks:

• Post your suggested activity as an Answer below (not a comment).
• Other people can Comment on that idea.
• Other people can Like (star) that idea.

In @cfastie's words (though he won't be joining us, boo!):

These can be ideas for activities that you would like to lead or activities that you would like someone else to lead (please specify).

This will allow everyone to better prepare (what to bring, what to expect, whether to stay home, etc.).

Ha ha ha. But for real, I'd also like to request that people state what questions they'd like to try to answer in a session -- or what ideas they'd like to explore!

We'll be doing this all in person on the "Marketplace" schedule grid, as we always do (if you haven't done this yet, no worries -- it's fun and easy). But this is a chance to share some ideas early!