It's the game that's taking the celebrity world by storm - even if the honour of participating is open to debate.
Cheeky DJ Chris Moyles has persuaded showbiz pals to too the world they have slept with him while they are giving TV interviews.
Already Billie Piper has slipped the line "I slept with Chris Moyles last night" into conversation, and Philip Schofield has also joined up.
But Fearne Britton got the better of Justin Lee Collins' attempt to join the club when she interviewed him on This Morning, when she beat him to it and said that "sleeping with Chris Moyles was the most bizarre experience of her life".
JLC replied: "You've slept with chris Moyles too? Oh I love to do that."
Whoever next?