Generally they are split between the quiz question style or physical challenge style (or a combination of the two). Physical challenges are the favourite of mine. Messy obstacle courses, or the contestants having to get messy to succeed. Feel free to borrow any ideas from the silly stories I write if you like.
A cooking show where two chefs prepare a full 3 course meal. Judged by a panel and the loser has to wear all the food. Of course the winner gets to decide how.