It's a sweet agave bar hidden in the fridge of a Mexican grocery store that use to be a laundromat. It doesn't get more Brooklyn than that but the tourists haven't found it yet so I highly recommend it. Music is really good and they have a great selection of mezcal. Felipe, the owner, also owns the adjoining restaurant Cerveceria.
For oysters & libations. The comprehensive oyster menu changes depending on what they can get that's fresh. If you know anything about oysters or just plain like them, this is without question the spot. Currently my favorite oyster (not always on their menu) is the Skookum.