I can think of so many I could be here all night. Basically everything GLaDOS says in Portal:
"Any contact with the chamber floor, will result in an unsatisfactory mark on your offical testing record. Followed by death. Good luck!!"
Almost every line in, Psychonauts:
Raz: "My name..."
Coach Oleander: "Begins with a 'd'"
Raz: ...is Razputin, but you can call me, "Raz".
Just as an example.
TimeSplitters, any game really:
Jo-Beth *kicks Cortez in the crotch*
Jo-Beth:"Hey! you're no Zombie"
Cortez: *high voice* "Yeah! I'm aware of that..."
