I just made my fourth visit to Supercore last night and finally remembered to post something about this little gem!
It's a cozy little place with a good selection of coffee, tea, beer, wine and SAKE.
their food definitely shouldn't be overlooked, either. they have a menu of small japanese dishes--and offer a $5.95 lunch special where you can choose any three, and it comes with a rice ball.
i had dinner there last night: mackerel cooked in sake with rice and cold spinach salad. the mackerel itself had a delicate and complex flavor and a moist texture--i'm still imagining the taste of it right now.
so anyway, check it out...it's on Bedford and South 2nd street. it's a nice escape from the rest of the williamsburg scene.
by the way, on sundays they have live music.