How about the opening monologue to MW3?SimpleChimp said:"The more things change, the more they stay the same. Boundaries shift, new players step in, but power always finds a place to rest its head. We fought and bled alongside the Russians. We shoulda known they'd hate us for it. History is written by the victor. And here I am, thinking we'd won. But you bring down one enemy and they find someone even worse to replace him. Locations change, the rationale, the objective. Yesterday's enemies are today's recruits. Train them to fight alongside you, and pray they don't eventually decide to hate you for it too." by Com. Shepard
I don't care what you say about the game, that is a damned good opening monologue.
http://www.youtube.com/watch?v=MgRIyVh0w9E
Just something about the way Makarov talks makes this so creepy and memorable.