Some of the best game shows come from the U.K., don’t they?
Golden Balls, Game Theory, … (scroll down to read the earlier post first)
Notice the differences between this game and the Prisoners’ Dilemma.
Additional reading, culled quickly:
Split or Steal? Cooperative Behavior When the Stakes Are Large (about this game)
Golden Balls: A Prisoner’s Dilemma Experiment (appears unpublished as yet)
Risk aversion in game shows (book)
Deal or No Deal? Decision Making under Risk in a Large-Payoff Game Show (with cites of earlier papers)