There's a lovely unique bird house, an exact replica of the apartment building, located in Ulm, Baden-Württemberg, Germany.
On my last tour through the historicl, so-called 'Fischerviertel', I have inserted a little break on a small bridge. And then I noticed this little bird house... innocently it sits on the balcony railing ; )
Well, it is particularly not very large, but it's, however, an exact copy of the apartment building, to which it's attached. Maybe, just maybe, I am mistaken and the house was built after the prototype of the birdhouse ;)