Quake lead to me meeting my wife, is hard not to fall in love with a girl that can headshot you from across the map while giggling.

Civilization taught me never to enter politics, as i would invariably end up becoming a genocidal monster.

Age of Empires made me become interested into ancient cultures, and how good they were at making other ancient cultures extinct.

Final Fight taught me that roasted chickens can be found in trash cans in back alleys and to beat up the homeless riding subway trains.

Carmen Sandiego made me realize that being a detective involves terrible work hours and worse plane hopping. And the prison guards are morons and let her out time and time again.

I learned EU and Asian geography via Empire: Total War. Er, Sweden is part of the 13 Colonies, right?

I kid, I kid. :P
Heh, Alpha Centauri taught me to never enter politics because I would sit around trying to be nice while everyone got progressively more powerful 'till they crush me.