"The artist who did this, Michael Grab, is a balancer of rocks. In an interview on Compliment Vices, he describes what happens when he builds these sculptures in front of live audiences, which, apparently, he's done a few times — in Costa Rica, in Italy. Once, at the Boulder Creek Path Festival in Boulder, Colo., a guy came up to him and said, "My brother absolutely does not believe these are balanced like this. He thinks there's bars or glue." He demanded proof that these sculptures were for real."

"'Everybody's watching, everybody heard the whole exchange,' Michael says. 'So I just go up and tap one in the middle and it just collapses. And everyone is like [gasp!] So I just like, get down, start making it again. Make it a tiny bit different.'"