Of course it spawns a wide bow of what could be named that way, but I prefer modern architecture and there I would try to "pull out" sights, one may not recognize with the bare eye or at least without the photographers eye. In other words: some kind of abstraction. I'm not an architecture photographer, but I do some photos of buildings from time to time and as I wrote, I prefer "living" buildings, not the abandoned ones. But I often end up in just documenting not even modern, but old architecture too.
Flickr shows pretty everything, what's written correctly in the Exif part and even if the objective wouldn't be known by the 5D, there would something like 17-40 mm be written below the name of the camera body.
For the equipment: Any equipment is useful. If you don't own a Canon TS-E 17mm f/4L you will not be able to do the stuff that (expensive) part is famous for, but you can do many other things, even with a 200 mm lens.