I love the bit at the end where Ibrahim (market trader) says it's "the hardest money I've ever had to work for" and Nick (charity worker) jokes "he obviously hasn't worked in the charity sector to try and get money", then the look on Nick's face when Ibrahim says he's going to respray his yacht!
I felt that Nick displayed a good mix of hot and cold rationality.
I found this to be a very interesting method of dealing with a modified Prisoner's Dilemma. In this situation, if both players cooperate they split a cash prize, but if one defects he gets the entire prize. The difference from the normal prisoner's dilemma is that if both defect, neither gets anything, so a player gains nothing by defecting if he knows his opponent will defect; he merely has the option to hurt him out of spite. Watch and see how one player deals with this.
http://www.youtube.com/watch?v=S0qjK3TWZE8