A few come to mind:

Fugazi in 1990, supporting Repeater at the Sokol Hall in Omaha. Fugazi was amazing and 3 local bands opened including a funk band called the Fish Hippos. It was the Fish Hippos' first show, and they were damn good. After that show they changed their name to 311 (although I've never really become a fan of theirs).

Corrosion of Conformity in 1987 at the Lift Ticket in Omaha. They were supporting the Technocracy EP and the place, a seemingly "regular" bar had a bunch of punk shows in those days, and only held maybe 75 people. Easily the most intense show and most intense (non-violent) mosh pit I've ever experienced.

Replacements in 1987 or 1988 at the Peony Park Ballroom in Omaha. They weren't so drunk they couldn't play and they played a cover of the Georgia Satellites' "Keep Your Hands To Yourself," which they screwed up about half way through and just stopped and moved on to the next song.

Beastie Boys/Fishbone/Murphy's Law in 1987 in Lincoln, NE. What a bill!! Damn, this was a fun one. I also got sent home from school the next day for wearing my Beastie Boys shirt that said "Get Off My Dick" on the back.

Hoodoo Gurus, in 1986 or 1987 at the Peony Park Ballroom. They were supporting Mars Needs Guitars! and opened for the Bangles. I stayed around for the Bangles' set, but what a let down after the energy of the Hoodoos.

Stone