OK, you need to try Priceline for Berlin. I got the Westin Grand for $65/night--one of the finest hotels I've ever stayed in. Pretty much all the known 4* properties are good, and people are getting the underrated Marriott as a 3*.

Berlin is less expensive than London or Paris, and huge and sprawling, but the mass transit is excellent, so don't worry too much about location. You can take an S-Bahn or U-Bahn pretty much everywhere you need to go.

Berlin's art collections rival--and perhaps even surpass--those of Paris. The Pergamonmuseum is a must, as is the Gemaeldegalerie.