2 very unique hotels in Berlin
This 5 star Radisson SAS Hotel in Berlin Mitte has in the lobby the world's largest cylindrical aquarium! It's 25 metres high with 2,500 tropical fish. Except for being interesting from an engineering view, it's also very relaxing to have an ocean view at the heart of Europe, and it's also very funny to see divers cleaning the aquarium while you're having breakfast. I highly recommend it to anyone visiting Berlin. At the time I visited, the best deal was an offer they had at their own website: http://berlin.radissonsas.com/
Propeller Island City Lodge is an extraordinary hotel with 30 different rooms! All rooms and objects were created by the German artist Lars Stroschen. Much more appropriate than "hotel" is the designation "living in a work of art". "Unique" is meant literally, for the entirety of all furnishings and other objects are custom-made. When I visit I'd like to stay at room no15: http://www.propeller-island.de/rooms_neu/room_detail/15/index.php