I don't know about you, but I often talk for my character in games such as Oblivion and Fable, where the character is mute.
Fable:
Mercenary: Need a good sword to fight beside you?
Me: No, I most certainly do NOT need a good sword to fight beside me. God dammit, stop asking.
Oblivion:
City Watch: Tidings, Citizen.
Me: I am the loving Champion of Cyrodiil, Master of the Fighter's Guild, Arena Grand Champion, and Daedric Lord Sheogorath. I am most certainly no mere "citizen."
You can also make comments on the nature of some of the things people say in your games. Much like the above, though it need not function as a reply.
Fable:
Alice the Housewife: Oh, doesn't my finger look sad without a ring on it...?
Me: If I've told her once, I've told her a thousand times.
Oblivion:
Countess Alessia Caro: I am Countess Alessia Caro, wife to Count Marius. I think Leyawiin would be better off if we removed all the dirty Argonians such as yourself. You wouldn't have a problem with that, would you?
Me: Now, who says something like that? How tactless would you have to be?
(No, I didn't say that out loud)
