When I worked for a music corporation called FYE (For Your Entertainment) I used to do a TON of shows. Ranging from being a line coordinator at OZZfest 04 and 05. I did merch stuff for people from Backstreet Boys to Dir En Grey to Slipknot and even Marilyn Manson. I've got tons of autographs (One in particular with a story from Zakk Wylde that I will NEVER forget. Not to mention Jason Newstead telling me to quit smoking cigarettes, while he's smoking a joint and signing my Newport pack all at the same time.) My autographs range from Click 5 to Megadeth, Dillinger, Mucc, L'Arc, Britney, etc., etc.
Working there was a fun gig. The only bad story I really have is when I did line work for a band called Mastadon. Fuck Mastadon. (Although I do have a ton of stories.)
Next concert I'm going to is a band called cKy!!! They're finally playing literally 20 minutes from where I live so I'm smacking it up like a heroin addict.
Best concerts I've ever been to? Coheed and Cambria at The Electric Factory, Slipknot at OZZfest 2001 (Broken ribs, dislocated left shoulder, black EYES, Busted open left shin... fun, fun.), Dir En Grey at the TLA and Modest Mouse as well. Forget where they were. Borgata probably.