I spent a week in Berlin about 20 years ago. Got to a complex that used to house the film studios where they made the propaganda films during the IIIrd Reich. It was run by a commune and they had a bar/theatre/artist studios etc. Great place with lots of concerts.
Found the water clock in the Europa Centre(?) fascinating. How can you spend ages just looking at a clock? - but I did!
Museum at "Checkpoint Charlie" was good and I believe it's still there.

Eddie