The same gesture as the
famous High five but a more friendly term that can be exclaimed without making one look/sound
like a high-fiving douche
bag.
"So these frat
boys in their Lexus' tried racing me in my
VW, and I totally let them
blow past just to watch the cops pull them over... Up Five!"
in lieu of an after-sex high five: "YEAH! I just banged the shit out of you! Up Five!"