The Guardian's List of the Top ten Berlin Cocktail Bars.

Berlin is FULL of cheap bars. I wouldn't even advise on trying to find one cheap bar in particular, but just head to a neighborhood known for housing young, indie types and the divey, cheap, and cool bars will be everywhere. Bar hopping and exploring in these neighborhoods is so much fun! Prenzlauerberg, Ost-Kreuzberg, and Freidrichshain all have a lot of nightlife in certain areas and most of it is "downmarket" with the occasional trendy cocktail bar thrown in to show proper gentrification. If you do an online search for any of those neighborhoods plus "bar" you'll find all sorts of guides to nightlife in those areas. I enjoyed quite a few but I don't remember the names of any of them (proof that I enjoyed them!) There is a Big Lebowski-themed bar in Freidrichshain that is near many other great dives, although that bar itself is kind of a letdown, as the owner/manager is really hostile and the theming is kind of minimal. Even the Mitte has it's share of divey bars - I spent an evening in a DDR-themed bar right across from the MuseumInsel below a train station, which was great fun until a group of English-speaking tourists on a guided pub crawl came in and made the place unbearable. Trust me - Berlin does divey, with a lot more regularity than it does "fancy" really. Berlin can be a really cheap place to eat and drink, more so than any other European city I've been to.

Some excellent advice here. Also look in the immediate area of the S-Bahn station Jannowitz Brücke for good, cheap eating places when it comes to traditional cooking as well as other cusines.