A pub in Brooklyn, NY has become one of the first to offer a self-serve beer ATM.
Randolph Beer has a whole wall of craft beers that will dispense with a simple card. At the end of the night, you turn your card in and pay the tab that it kept track of.
Not sure how it makes sure you aren't over served though, because this could be bad news after a few beers and start swiping. I've had a few nights where my ATM card felt like a beer ATM for the whole place, when I looked at it the next day. Plus, I can't even be responsible with that card!
Me trying to leave that bar: