A phrase to let someone know that they have stolen your joke right after you said it, and potentially generated more laughs than you did.
<origin> After a game of volleyball someone says 'jump the net' nobody hears it so someone else repeats the joke a bit louder and gets a lot of laughs...
Shaun: The female wookies are the ones with brazilian's
Craig (louder): The female wookies are the ones with brazilian's
Everyone: hehehehehehe, good one Craig!
Shaun (to Craig): Jump the net...