All I can say is I will NEVER stop beating myself up for not getting tickets to Rock The Bells in 2007 - http://www.wutang-corp.com/news/article764.html
Someone at my work at the time was selling a couple tickets at cost and I passed on them because I was like "oh yeah, I get some later" and it never happened because they sold out everywhere. Even thinking about it now makes me sick to my stomach. I f***ed up.
I live in the SF bay area and this was the SF line up:
Rage Against the Machine
Mos Def + Talib Kweli
Jedi Mind Tricks
Very Special Guest Artists:
*Plus Special Surprise Performances! (Hint: It was A Tribe Called Quest)
I would never forgive myself.