One of the first bands I met was Cannibal Corpse. I was walking to my car after the show and I saw them outside of their bus surrounded by a pretty big group of people. Some friends and I walked up and talked to them about the show and World Of Warcraft and what not. Alex was talking to the same group of dudes for quite a long time and didn't seem like he was irritated at all. A kid who I think may have been mentally challenged walked up to Corpsegrinder with a huge sword and he signed it for him. It's awesome that one of the hugest, most influential death metal bands around are is filled with good people who actually appreciate their fans.
Amon Amarth was also really cool. It was their first time in Oklahoma when my friends and I saw them and they really seemed to enjoy it. Olavi gave me shit along with my friends because I don't like Manowar, and they signed a bunch of shit for everyone and were really appreciative.
I could type a bunch more about all the other bands I've met, but that'd take too long, so here's a list.
Piotr and Paul from Vader
Ethan from Lecherous Nocturne
Ross and Rob from Immolation
Karl Sanders from Nile
Elizabeth from Dreaming Dead
Doc from God Forbid
David and Rob from Machine Head
Michael and Derek from The Faceless
Mattie from For Today
Bryon from God Forbid
Roope from Children Of Bodom
10-22 Kansas City Gojira/Mastodon
10-30 Denver The Black Dahlia Murder