First: Laurent Garnier in the dive nightclub I worked in, in 1997 as a wide-eyed 15 year old. Sublime, tempted to make it my best, but the fact I didn't actually pay to go rules it out.
Best: Jay-z and Kanye, Watch The Throne Tour, 02 Dublin, 2012. Went as a favour to a mate, liked Jay, not arsed about Kanye. Fuck me, what a show. Mindblowing.
Worst: Robert Miles (he of Children fame). Was a real coup for the club to get him as he very seldom played over these waters much. He refused to acknowledge the tunes he was known for, and played beatless ambient psy trance for two hours to an empty room at £15 a head.