Free spirit alert! This guy is on some good drugs and just wants to dance!
Indeed, SFist is conducting an open investigation into what substances (if any!) this shirtless gentleman may have ingested. Let us know if you have an inkling by taking a look at this video of a few interpretive moves he deployed during an (excellent) set by Hot Chip on Sunday.
The drugs may also have been long-lasting, because there are reports of this guy doing exactly the same shit on Friday. Did you notice him?
Last, for further context, this creature was taking a nap about ten paces back.
There you have it!