C'mon now, we all have a story where we blew it. I'll start:
Roy Orbison - during Springsteen's "Tunnel Of Love" performance at the L.A. sports arena in 1988. R.O. was walking in the bathroom (ALL BY HIMSELF) as I was walking out, and I had no sharpie, no tour book, no nothing. I ran to my seat, grabbed a sharpie and a tour book but he was no where to be found. He died in December of that year. The only time ever I encountered him and I got caught with nothing in my hand. NEVER, have I been to a concert since where I do not have the goods ready.