I'm wicked old, so my list would be massive, but here are some highlights. On account of my age, I'm not sure of all the dates/years, lol:
Porcupine Tree/Steven Wilson solo, 2007, 2009, 2012, 2013, 2014, 2015 in various cities, among them Albany, N.Y., Chicago, Cincy, NYC, Boston...I so love this man and his projects.
Alice In Chains: too many to count
Jerry Cantrell solo tour: five times, I believe. Best show was at the Electric Factory in Philly.
Pearl Jam: too many to count
Soundgarden/NIN: Red Rocks Amphitheater, July 2014. Wow, just wow
NIN: too many times to count. Best show is a tie between the House of Blues in Atlantic City and the Electric Factory in Philly. In both cases, Trent went on epic rants/instrument destruction.
Metallica: too many times to count. Vegas and NYC and Orion festival would probably be the highlights, though there were some epic Philly shows as well. Boston rocked because I won a meet and greet, so that was special. Minnesota was also great because I got to see them with a CreedFeeder.
Primus, NYC (2007, maybe) Wildest pit I have ever been in. I had to vacate!
Floater, New Years Eve 2006. Finally go to see this West Coast band, which is a favorite of mine. Hung out with message board friends. Epic, epic show.
Eric Clapton, 2004, I believe. Me and Mr. Johnson tour.
Tool: too many times to count. One of the best was at the Gorge amphitheater in Eastern Washington state. Freakin awesome venue and a stunning show.
A Perfect Circle: 14 times, I think. First show was the first time seeing Maynard in the flesh...It was in Pittsburgh at Duquesne University. Show in Rochester was completely, insanely off the hook. Maynard was out of control, but in really good way, haha.
Opeth: I think I'm in double digits now, but my favorite show was the 20th anniversary of Blackwater Park, my favorite Opeth album. They played it in full, and even though the venue (Terminal 5 in NYC) was complete crap, I thoroughly enjoyed this show.
Alter Bridge: numerous times. I just love Tremonti. He's got a solo album coming out. I hope there will be a tour. It's been a while since I've seen him.
Steve, way cool on Louis CK!
I actually saw Louis Black at Summerfest in Milwaukee a few years back. Funny as hell!
Ok, I will stop now, as this could go on for days.