Moralityball
Moralityball is a sport / social experiment based on the Prisoner’s Dilemma. Teams of two must collect a certain number of tennis balls from a common pile within a time limit; unfortunately, it’s much easier to steal them from your neighbor than to go get them yourself.
The game debuted at the DCGames Fest 2012. Read all about it and watch videos of the game here.
The rules allow players to defend their base, steal from neighbors, or collect from the pile. Stealing is almost always the easiest way to get points, and the points are redeemed for prizes at the end of the game.
There are, in fact, at least enough resources for every player to finish with points, and that’s actually the most efficient solution. Players can negotiate with each other to try to reach this goal, but that usually ends up being more difficult than expected