Person 1: So, what'd you do last night?
Person 2: Your Mum.....ZING.

(although you usually have to say somethign funnier than this example)

Person 1: Your room smells like ass.
Person 2: That's because you're in it. ZING!

inj. example, any of the following lines from National Lampoon's Christmas Vacation may be followed by the exclamation "ZING!"
neighbor: Hey Griswald, where you gonna put a tree that big?
Griswald: Bend over and I'll show you (...ZING!)
neighbor: You got a lot of nerve talking to me that way.
Griswald (looking at neighbor's wife): I wasn't talking to you (...ZING!)

Hey. These eggs are a little hot. I'd like them a little colder. Cold. Like your heart. Zing!"

Frank: I hate pretending the play our intruments (on the set of music videos), I feel like Ashlee Simpson....ohhh zing!

Angus: your gay
Donald: your mums gay
Dylan: ZING!

check the bumper on that girl she definately gets my zing rating