I've gotten to watch a fair number of soundchecks as the only civilian in the room - it really is a magical experience. I've become friends with the guys in my favorite band and it's lead to some really magical experiences, like the time I got to play guitar for the last minute or so of a sold out show at the Ryman in Nashville (See https://www.youtube.com/watch?v=8tCrreXh0Pg&list=RD8tCrreXh0... starting at about the 6 minute mark)