I can't believe it Big Surprises in Music

Right, I need to put a few things in perspective first.

1) I love to listen to many things from Bach to Strawinsky, Coltrane to Sun Ra, Beatles to Zappa, Brel to Waits, ... you'll get the gist.

2) Since a number of years, there is an open air gig called the Hurricane Festival, this year featuring the likes of Faith No More (you read that correct: reunion), Nine Inch Nails, The Pixies, The Mars Volta, ... guys who know how to do a live performance properly.

So I was watching Hurricane 09 on the TV when on stage walks ... Kate Perry and starts a cooking performance. Man, this had nothing to do with the polished video clips we know her from. More important, this singer has a-b-s-o-l-u-t-e-l-y nothing to do with the likes of dreadful plastic voiceless JLo. Kate sure knows how to rock. In the middle of "I Kissed A Girl" she is hovered into the crowd (ten thousand hands stretch out as they had never been stretched out before, go figure) and, yes, finds herself a girl to kiss in the crowd.

That was one huge misconception on a singer I had to revise. Any other jaw-dropping surprise in music you like to relate?
Many years ago I saw Springsteen do a solo acoustic concert in Berkeley. I was shocked to learn that he could really, really play the guitar. I had seen him many times before in his typical giant three hour concerts and was a huge fan but never thought of him as a great musician like my other favorite guitarists like Leo Kottke, Eric Johnson, and later Kaki King. Bruce showed creativity and mastery of his instrument like no other that night and it remains my favorite Bruce concert ever. "Adam Raised a Cain" rearranged by him and played on twelve string was a complete jaw-dropper.
I saw Springsteen do a solo benefit show at the Shrine Auditorium in November 1990 with Jackson Browne where he played the solo piano!

My perfect "Big Surprise" is top end talent playing small shows. Shows that come to mind:

Jimmy Buffet walking into a bar in Solana Beach post concert to a crowd of 25 circa 1978, Paul Kelly playing solo acoustic at the Hotel Cafe in Hollywood to a crowd of 12 in 2006 (he is considered the Bob Dylan of Australia); and Van Halen playing in a bowling alley in Covina to a crowd of 4 people in 1975(I saw David Lee Roth later and reminded him of that gig).
I have two:
The first was circa 1984 when a friend and I went to see a band called BHLT here in Atlanta at the Moonshadow saloon. BHLT was Dickie Betts, Jimmy Hall, Chuck Level, and Butch Trucks playing jazz fusion in the same vein as Sea Level. The second was early 80's when I was visiting Nashville and met my sisters at the Exit/Inn for a couple of beers. They were attending Vanderbilt at the time and it was about 3:30 in the afternoon. All of sudden, Jeff Beck walks in with his guitar. He was in town recording with Rod Stewart and had wrapped up their session and wanted to have a couple of beers and play a few songs. It was me, my two sisters,the staff, and Jeff Beck.He made incredibly melodic music using a beer bottle as a slide for his guitar sitting at our table. As word got out onto the street, the crowds came rolling in. When I left about 6:30, there were about 200 people there. Beck could not have been nicer and just seemed like a regular guy who was really into making music.