I know this will get ripped apart, but here goes.
1. Pink Floyd, 1994 at Arrowhead. They were without Roger Waters, but still an awesome show.
2. Grateful Dead, 1991 at what was then called Sandstone Amphitheater in Bonner Springs. It was the Dead... what more need I say.
3. Negative Approach and Circle Jerks, 2006 at Waterloo Park in Austin, TX. They were the last 2 acts on the punk stage at the festival, and the only ones we cared about. It was only Negative Approach's second gig back after reuniting 25 years from their last, but they didn't miss a beat.
4. Old 97s, 2011 at Cat's Cradle in Carrboro, NC. Teddy Thompson opened and put on a fine show as well.
5. Sting, 1988 at Starlight Amphitheater, Swope Park in KC. He returned for a second show of the year during the Jazz Fest. His first solo tour so plenty of Police standards along with his own stuff.
And an Honorable Mention must go to the first concert I ever attended: Johnny Cash, sometime in the late 70s, at what was then the Shawnee County Fairgrounds in Topeka. The stage was set up in the front straight of the 1/4 mile dirt track and we sat in the grandstands. I was too young to really remember much, but it was Johnny Cash. Doesn't get much cooler than that.