Emob78: Pretty much any open ended world. The freedom to do what you want is nice, but it's sad to see so many gamers take the Machiavellian approach so easily. Sure, it's nice to tip your toes in the darker waters once in a while, but gamers these days have become exceedingly cruel, impatient, and well... kind of evil. The ragequit syndrome you see on videos on youtube is just a symptom. Playing violent games might not make someone violent, but it sure seems gamers enjoy playing on the dark side a bit too often.
I'll refrain from putting on my paragon helmet and declaring a crusade here. Just remember what Yoda said, 'the dark side is easier, more seductive. But once you start down the dark path, forever will it dominate your destiny. Consume you, it will.'
You can't expect people to have any empathy towards digital NPCs...and without empathy, human beings are naturally evil. That is why sociopaths are dangerous... So I don't think embracing the dark side every time you are playing games will make you turn to the dark side in real life because of empathy.