I am of a different era from a lot of you
lots of really good tech death metal shows come to mind. But my favorite, most memorable by far, totally out of norm, Lionel Ritchie in Camden NJ. My friends and I were given free tickets. Middle of the summer and had severe storms that night. They paused the concert in between acts, but resumed shortly after. There was spider lightning all across the sky all night and it was absolutely spectacular. Maybe not the safest, but wow, what an experience.