Musashi Japanese Imbiss on Kottbusser Damm has a reputation for serving some of the best sushi in Berlin. Hardly a restaurant as places are extreemly limited in such a tiny space, it's often crowded with people wanting their fill of edamame, fresh sushi and green tea ice cream.
Easier in the summer as you can also sit outside, this is not a place to hang around dining all night, the turn over is quick and you may just want to take your sushi away with you and eat somewhere a little less hectic.
When we say prices are low, we mean really low. Tea is 50 cents, water €1 and beer €1.50. The Angebot 3 on the menu is only €6.50 for miso soup, a main dish and a cup of sake! They also have some good vegan and vegetarian options.
Basically if you simply want good sushi prepared by Japanese chefs and don't mind a crowd, this is the place to go in Berlin.