I voted for spending the night with a notorious celebrity. It'd be Victoria Coren. She's not really very notorious, nor a celebrity, but she's quite lovely.
http://en.wikipedia.org/wiki/Victoria_Coren
She's better looking than that photo suggests, she writes for two decent national newspapers, presents a great show on BBC2, she tried to make the best hardcore porn film ever, and she won £500,000 in the European Poker Tour. Quite frankly she's the most perfect woman alive.