I like mind games, I think we could elaborate on this ^_^
First I'd gather players who want to participate and note their names down, then each round select 2 players and PM them that they are chosen (but not telling them who the other is).
Each of the 2 players can select no prize, medium prize or big prize.
If both players select no prize = both players get big prize.
If player1 selects no prize and player2 selects medium prize = both players get a medium prize.
If player1 selects no prize and player2 selects big prize = player2 gets big prize.
If player1 selects medium prize and player2 selects medium prize = both players get a medium prize.
If player1 selects medium prize and player2 selects big prize = player 1 gets a medium prize and player2 gets nothing.
If both select big prize = both players get nothing.
