2. Agent
Here's a game that's just baffling in its abandoned state, given that it comes from the venerable Rockstar Games, who essentially develop a license to print money every time they release a new game. While the majority of Rockstar's games are in a contemporary timeframe, Agent was to go back to the 1970s for an espionage tale that would see you fighting through the Cold War and actually changing history (though how far this idea went is anyone's guess). At present, details remain confused and sketchy about the title's future; we hoped to see it possibly re-purposed as a PS4 title at E3 last week, but no announcement was made. Though Rockstar has stated in the past that they are in fact still working on it, given GTA V's imminent release, it's easy to see how this one has gone on the back burner.