Though I'm sure I've seen worse, one performer I'll always remember is Ben Kweller opening for Lupe Fiasco at UC San Diego's Fall Fest in 2008. He seemed upset that the crowd was anxiously anticipating Lupe, so he'd keep saying: "And now... Lupe Fiasco will be up.... after a few more songs." He also complained on stage about how Talib Kweli sampled one of his songs for "Ms. Hill". Overall, a bad attitude and what I would call a performance that he couldn't care less about is what led fans to boo him throughout his set.