Cheap and Interesting
Berlin hasn't been my favorite city I've visited, but with that said I liked it quite a bit and would recommend it for a brief visit. The food is cheap and quite good if you know where to look. I loved the beer gardens and bars. Getting a chance to see the Berlin Wall was fascinating and there is a lot of green space to lounge and open roads to explore.
Insider Tip:Go to the Holocaust Memorial Museum. It was the most moving museum or memorial experience of my life and I have been to many.