I remember when I started with photography, seeing photos like this one and just not understanding how it was taken. The view from the lens I had (18-200mm) just never looked like that. Of course than I got a nice wide angle lens (10-20 at that time) and I understood immediately. Until one tries one out, one will never understand the difference few mm of focal length can make. The view is just do different.
For this shot I went with the 16mm focal length (of course on a full frame sensor :)). One can get quite an interesting view, by lowering the camera down and pointing it up. This is a HDR from 7 exposures, created in Oloneo Photoengine, finished in Photoshop. Photo taken in the Hungarian state opera in Budapest.