http://en.wikipedia.org/wiki/Prisoner%27s_dilemma
Here is the fundamental problem called the Prisoner's Dilemma, which led to the development of the game theory by John Nash. A fairly interesting observation, it supposes that two prisoners are cught for a crime and are offered 6 months of jail. Alternatively, they could confess to a bigger crime and go Scott free, dooming the other to 10 years in jail. The Nash equilibrium proves that both shall confess, leading to a mutual loss due to lack of communication!
