My wife, daughter and I spent a few days in Berlin last week. For anyone who has never been, I recommend it. Berlin is a really nice city with a lot of history. Unfortunately, with a 1 year old, it was hard to really see and appreciate all of it. We didn't get to see see the DDR museum (a look at life in East Berlin in the Cold War) or really look in depth at Cold War stuff. We had a brief look around the Topography of Terror (a museum on the site of the Gestapo and SS HQ) which is just along from Checkpoint Charlie.
However, one thing we did go and see was Classic Remise. It is essentially a car storage facility for rich people but it is open to the public and anyone can go in there and take a look around. There are kinds of cars in the there - rare exotics, Ferrari La Ferrari and everything in between - some very cool stuff. I would highly recommend anyone going to see it if you go to Berlin. It a bit outside the centre though (you can get there by U-bahn and a 10-15 minute walk or a bus fairly closely). I would recommend setting aside a morning or afternoon for it. Without kids, and with time, you could easily while away 2-3 hours there just gawping at the gorgeous metal there.
Once I figure out a new hosting site, I'll get a few pics up.