In Mass Effect, in the Earthborn sidequest, there is a moment in which a member of your old Earthside gang will show up on the Citadel, and ask you to use your status as a SPECTRE to get another member released from custody by the turians. Go into the bar, and tell the turian guard that you want the human prisoner released. His response: "We all want things, human. Desire forms the basis of organized society. That being said, the xenophobe will remain in custody."
Just about any long conversation with assassin droid HK-47 in the Knights of the Old Republic games will result in some chuckles - for instance, when he explains the origin of his use of "meatbag" to describe organics. My personal favorite, though, was when HK-47 attempted to define love, in the second game: "Love is making a shot to the knees of a target 120 kilometers away, using an Aratech sniper rifle with a tri-light scope. ... It consists of two beings coming together against great odds to achieve a singular result."
In Halo: ODST, there is one side-mission that consists of Dutch, a sniper, trying to get across the Uplift Preserve park. When he reaches the far side, he has to drive his vehicle through a gap in a wall - that dumps him out some distance above the streets of New Mombasa. In a cutscene, Dutch bails out in time, and turns to see his vehicle piled up against a building nearby and on fire. "Lord," Dutch says semi-reverently, "I didn't train to be a pilot. Please tell me I don't have any more flying to do today."
At that moment, a broken combat drone comes screaming out of the sky and crashes into a nearby monument. Dutch hits the dirt for the crash, then gets up, looks to the sky, and asks, "Was that a 'yes' or a 'no'?"
Behind him, the vehicle he rode in on explodes. Dutch responds with a quiet, "Amen."
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Sodium is a metal that reacts explosively when exposed to water. Chlorine is a gas that'll kill you dead in moments. Together they make my fries taste good.