That's Victor Foglio (Phil & Kaja's son), who alertly noticed the empty table, started drawing sketches, and put up a sign offering to sell them for $1 each.
And people were buying them, too. Clever kid. And he likes trains, too.
Steam Powered looks like it should be a fun little convention. I'll be back down there tomorrow to hear about the Babbage Engine and other things of that ilk.