Here's a good one from Red Dwarf. This involves Holly, the Red Dwarf SuperComputer (no, not me lol - it's a man, for a start) and one of the several Humans who live on the Ship, Dave Lister.
Holly: Busy, Dave?
Lister: Well, yeah. I am, actually.
Holly: Oh, then you won't want to know about the two super-light-speed fighters that are tracking us.
Lister: What?!
Holly: I'll leave you to your bubble blowing, mate.
Lister: No, Hol, come on, come on.
Holly: They're from Earth.
Lister: Three million years away?
Holly: They're from the NorWEB federation.
Lister: What's that?
Holly: The North Western Electricity Board. They want you, Dave.
Lister: Me? Why? What for?
Holly: For your crimes against humanity.
Lister: You what?!
Holly: It seems when you left Earth three million years ago, you left two half-eaten German sausages on a plate in your kitchen.
Lister: Did I?
Holly: You know what happens to sausages left unattended for three million years?
Dave: Yeah. They go all mouldy.
Lister: Your sausages, Dave, now cover seven-eighths of the Earth's surface. Also you left seventeen pounds, fifty pence in a bank account. Thanks to compound interest you now own ninety-eight percent of all the world's wealth, but since you've hoarded it for three million years nobody's got any money except for you and NorWEB.
Lister: Why NorWEB?
Holly: You left a light on in the bathroom. I've got a final demand here for one hundred and eighty billion pounds.
Lister: A hundred and eighty billion pounds! You're kidding!
Holly: April fool!
Lister: But it's not April.
Holly: Yeah, I know, but I could hardly wait six months with a red-hot jape like that under my belt.
^ THAT is the funniest thing I've ever heard, I'm not kidding. I've watched that episode so many smegging times it's frankly frightening, and it STILL rocks! ^_^ I'll leave the facial expressions to your imagination, because that's half the beauty of quotes.