A war game played in actual real time, where wars take months to years of playing time. Bonus points for playing as a soldier why needs to patrol around the camp for months before dying from a bombing, without ever seeing an enemy soldier.
A game about being a soldier in a time of peace.
A game about some criminal activity (e.g. piracy, street races, theft, whatever) where the game prevents you from actually breaking any laws, including the really little ones.