Whats the weirdest concert you ever attended?

I have to say this is only bought up by one particular concert I attended in 1970 in Birmingham England.
I went to see a German band called Faust. They had a bit of a reputation for being more weird than most, and that's saying something given other bands around at the time and had an underground following along with Henry Pig and Hatfield and the North.
So.... I was in row two and eagerly waiting for the show to start. The auditorium was completely dark except for the lights on the amps. At each side of the stage there was a big old 36" colour TV set and a pinball machine.

In due course, everyone assumed that the band came on stage as the light on the amps went off in sequence as if someone was walking past them. Then, eventually, odd sounds started emanating from where we assumed the band was. Still no lights. Then the TV's burst into life and were showing a different channel on either side of the stage. Still no sign of the band.
Next a guy walks on stage in just his underpants (1970's Y fronts)and starts playing the pinball machine. Every time he used the flipper the TV channel changed.

This was how the whole one and a half hours were spent until the guy on the pinball either got bored or the band got bored but he just walked off, the music stopped and the lights on the amps flickered again so we assumed that the band had left the stage.

During the course of the "concert", there was all sorts of aromas of illicit substances. To put the icing on the cake, about half way through, a woman in the front row turned round to me and said "would you hold this for me" offering a newly lighted special cigarette. After passing it to me she proceeded to turn back to the front, lean on the stage, have very quick very rough sex doggy fashion with someone I can only assume was her partner and then ask me for her joint back!

My head was really messed up for weeks and I'm still not sure if it was the concert or the side show which was to blame.
Captain Beefheart and his Magic Band, Feb 4, 1972, Irvine Auditorium Philadelphia.

Little Feat with Lowell George was the opener.

Rockette Morton came on stage with a toaster on his head, halfway through the first song, toast popped up. His way of saying 'a toast from Rockette Morton.
Frank Zappa at the Filmore East in 1976. He played a couple of songs we knew, we were all big fans, and then he launched into some complex difficult and interminable orchestrated piece . He had a fairly large orchestra working with him that night. So after a couple of what seemed hours he finished this "song" and said that the concert was being recorded for an album He then turned back and scolded the big band to play it again but with fewer mistakes. No amount of any substance could compensate for his commitment!
A few stand-outs for various reasons. I ushered at a Milwaukee theater called Uptown back in the early to mid-seventies. The tubes put on a very bazaar show. Much stage activity, which was well above my intellect.
Springsteen's Bomb Scare concert. The theater emptied of audience had police, dogs and bomb specialists rummage through for nearly 2 hours. Amazingly, Springsteen came back on played well into the wee hours...appearing far more inebriated.
I saw the Who at Tempe University for Who-loween. I believe it was 1981, with Mellencamp as one of the opening acts. A number of audience members expressed their impatience with the openers, some carrying placards requesting The Who are the best, forget the rest. Somewhere in Mellencamp's set he got nailed in the head by a thrown bottle. He went down, the band barreled off stage. What seemed like lapse of an hour, they reappeared, Mellencamp's head bandaged, wearing a hard-hat. The Who finally came on, they said no hello's, played their music, and left.
My wife and I recently saw Peter Noone, as Herman Hermit at Wisconsin State Fair. Her comment watching an audience of nearly 400, mostly 50-70 year olds bobbing their heads to 60's pop music was as strange as it gets.
One more. About 5 years ago The Flaming Lips opened their show with huge balloons and giant balls rolling atop the audience. Followed by an animated image of nude dancing woman eventually reclining into birthing position...legs bent and spread. A stairway was strategically placed to allow the band to enter through the appropriate opening.