And, oh, but The Majestic was a hip place. My mere presence there was significantly squaring the room, as evidenced by the fact I'll actually call myself a ``square'' even though I don't think anybody but cartoonishly outraged parents in TV shows contemporary to Dobie Gillis ever used the term. At one point 
bunny_hugger warned me not to look now, but there was a guy with an extremely ironic moustache right behind us. I took a discreet look later and, yes, he had a reedy thin heavily-waxed handlebar moustache, of the kind that hasn't been worn sincerely since the Punitive Expedition except by my chiropractor uncle in Indiana [1].
The opening act, 21 Pilots, was two people, and they may not have been the best musicians but they were quite energetic, showy performers with a good understanding of working the crowd. They came out wearing skeleton-figure hoodies and went through their half-hour set playing music loud enough to rattle the earplugs out of my ears (my right ear would be a problem about half the night) and doing stunts like getting up on the piano and doing a backflip.
The second act, Walk The Moon, was who we were really there to see. They sounded great and while they didn't go for obvious stunts like gymnastics or (as the headliners, Neon Trees, would) calling out for specific audience participation, there were some anyway. One of their visual gimmicks is face painting, and there was a woman going through the (quite long) line waiting for admission offering paint to attendees. bunny_hugger got a little sideways caret. I got overlooked because see above comments about squareness. At the merchandise table, too, people buying stuff were given dabs of face paint. It may seem like a simple gimmick, but, boy, they had fans. They played about 45 minutes and I recognized most of the songs from their album or, even better, from bunny_hugger singing. I reliably feel like smiling when she sings.
Neon Trees, as the headliner, had all the accoutrements of fame, though what most intrigued me was the large backdrop with their name (in Avant-Garde typeface with weird spacing between rows) and logo. Where do you get something like that, and at what point in the career is it needed? They had the most energetic performance, with full lighting effects and, I believe, also some fog machines. They also set things up for an ``early celebrity death'' moment by having the lead singer swing the microphone around his head, then lower it so the cord wrapped around his throat. It might please the crowds but all I see is an unsafe working procedure.
[1] Also that dangerously violent spokesman for the Handlebar Moustache Wearers of America that turned up that one Bloom County strip, and who looked stunningly like my uncle. (The spokesman ended up saying he was so frustrated he wanted to strangle a manatee in the nude or something to that effect. So far as I am aware there are no manatees in the region of Indiana where my chiropractor uncle lives.)
Trivia: By 1886 Eastman created a camera with the roll-film holder built in. The model known as The Detective went on the market for $45, but no more than fifty were made, and most appear not to have sold. Source: Wondrous Contrivances: Technology At The Threshold, Meritt Ierley.
Currently Reading: Magnificent Failure: Free Fall From The Edge Of Space, Craig Ryan.