Cheryl B.
Yelp
Tucked away in an innocuous business park, among a catering company, and an Agape church, you will see a giant piece of the Berlin wall. We're talking 2.6 tons of Berlin wallness just hanging out outside. Bonus is, you can't miss the place. There is plenty of parking, so take care of that, remark how awesome the giant cemetery next door is, and go inside, past the Berlin wall, and head upstairs. (where the temporary exhibit is) downstairs. And this is just the beginning of the awesomeness of this place. Downstairs houses the archive and the temporary exhibit, a informational, creative exhibit of a piece of life in East Germany or the Soviet Union. Nooks and crannies of soviet goodies abound.
The full title, "Wende Museum: Museum and Archive of the Cold War" is appropriate; the small museum consisting of only 3 or 4 rooms is not even the main attraction. Downstairs is an archive of over 100,000 items from East Germany and the former Soviet Union. Boxes upon boxes of amazing memorabilia from the Soviet Union. If you plan ahead, you can get a tour of the archive and see some great things.
The museum boasts famous Soviet paintings, posters, sports memorabilia, military uniforms, flags, and soviet trinkets, like tree decorations (little soviet astronauts, soviet stars), paper weights, East German spy gear, trophies, books, and magazines.
This place is great and I don't think there is another museum like it, but it serves a niche market. If you aren't interested in Eastern European history, literature and culture from 1945-1991, one could find it boring and esoteric. It is not a flashy museum; they do a great job, but it's a young museum founded by an academic. It doesn't try to entertain patrons with bright lights and fancy simulations, but there is so much great history behind everything, it doesn't need it. I recommend going when you can go on a tour because the acquisition of some of the items has as much background as the items themselves.
Finally, the founder, Justinian Jampol, is the brains behind the operation and awesome. Check out this article for more excellent reasons to spend an afternoon at The Wende.
http://www.spiegel.de/international/0,1518,352278,00.html
They also have internships and some decent research opportunities, if you are into that sort of thing :)