I will list some highlights for you because I like you have seen too many to list.
My first show, Korn opened for 311 in '93 on the grassroots tour.
I have seen Dave Mathews many times. Godmsmack at least 9 times. Zombie (Both White and Solo), Chevelle, Seether, Halestorm, Five Finger Death Punch, Adellita's Way, 30 Seconds to Mars, Rev Theory, Hollywood Undead (who is bad ass live I might add), Cypress Hill, Manson, Slipknot, Stone Sour, Fall out Boy, Filter, Arron Lewis (Solo), Staind (many many times), Black Label Society, Alice in Chains (Both black and white singers), Nirvana, Bush, Julian K, Orgy, Blues Traveler, Candlebox, Cold, Crossfade, Papa Roach (I have pictures with them), and lots more that aren't coming to me right now.
I started seeing shows in High School and didn't stop up until a few years ago. My wife and I planned our vacations around rock festivals around the country for a while. The highlight though is a few years back she won a chance off the radio for an all access pass to Linkin Park. I got to go back stage and meet them, then was on the stage and in the camera pit during the show.
Some of them are blurry but you get the idea. I had a really crappy camera back then.