Question a bump that provided no answer but I will contribute:
1- oscar Springsteen - Sprint Center, 2008 - wasn't even a Springsteen fan, the guy is simply the best.
2 - Wilco - New Hampshire Street, Lawrence, KS - first Wilco live show, been in love ever since.
3 - Arcade Fire - Grant Park, Chicago, Lollapalooza - first performance of The Suburbs ever. Incredible. 5 rows from the front. Pissed in a Gatorade bottle to keep my spot.
4 - Avett Brothers - Red Rocks Amphitheater - by far the best venue I've ever been to. Watching the Wiggles would be worth it here. Portugal The Man opened. Saw them here a year later and John Prine opened
5 - Flaming Lips - Wakarusa - Lawrence, KS (before the festival moved away) - I was 18 and have never been around so many naked people in my life. First mushroom trip. Incredible showmanship. Covered "Song Remains The Same" by Led Zeppelin