I just got back from 5 nights in Berlin. I tried to stay at Pension Funk, but it was full, as were many other hotels, thanks to a big conference going on at the fairgrounds. I ended up staying at the Ibis Budget Potsdamer Platz, which was quite spartan but reasonable value for the money. It's somewhat misleadingly named, as it's not very close to Potsdamer Platz - close to Anhalter Bahnhof S-Bahn station. I did a day in Potsdam visiting the various palaces. One slight backdoor place there is the Marmorpalais or "Marble Palace", which is some distance away from the other palaces but very interesting. Warning to sightseers: the central section of Unter den Linden is pretty much a building site at the moment due to construction of the new U5 subway link line between Alexanderplatz and the Brandenburg Gate. The other warning is that the streetwalking in Oranienburger Strasse is much more blatant and aggressive now than it was last summer, with a woman outside pretty much every restaurant from Oranienburger Strasse S-Bahn down as far as Hackescher Markt and lone men liable to be repeatedly propositioned. Given the similarity of the womens' costumes, it's obviously being organised from somewhere.
Most notable meal of the stay was at a place called "Renger Patzsch" in Schoeneberg, which is a slightly posher version of German beer hall cookery - more interesting food but rather smaller portions. I do recommend it, though. Main and dessert, a couple of glasses of wine and a soft drink came to just over thirty euros. There's an interesting arrangement at the Maerkisches Museum (local history) at the moment, with rooms themed by streets relevant to the subject. So, for instance, "Unter den Linden" is the Frederick the Great era, "Wilhelmstrasse" the Third Reich, and "Oranienburger Strasse" is the Berlin Jewish community. An underrated site I visited this time is the "Berliner Galerie" near the Jewish Museum. It has a permanent exhibit of "Berlin Art 1880-1980", with a particularly interesting Dada room. As I've said elsewhere, the Berlin Welcome Card isn't really worth it, but the three-day Museum Pass to all Berlin's city museums is very good value at nineteen euros, and will almost certainly save money. Something I've suffered from on earlier trips to Berlin and keep forgetting: Berlin bus drivers will not wait for you to get off the bus if you wait until it has stopped to descend the stairs.