A term stemming from hockey that means to do something in exuberant fashion (as in hockey, where scoring off the crossbar is going "bar down").
Guy A: Dude, are you still on the same beer? Bar Down!
Guy B: BAR DOWN! *proceeds to chug
Guy A: What'd you do this weekend?
Guy B: Took a little vacay
, went bar down on some skiing
Guy A: BEAST