Here are the two favourites of mine, neither of which, I'm afraid, are particularly great photographs. The first was one I took after I installed the lighting - just the layout's lights illuminating the scene, hence the slightly indistinct and slightly grainy appearance:
The other one I took about four and a half years ago, while there was still a lot of scenic work to be done. It isn't a digital photo rendered in black and white - it was taken with a 35mm film camera loaded with black and white film, Ilford FP400 if I recall correctly. As I said, not a great photo, so why is it one of my favourites? It's just that, rather appropriately for a three rail layout that uses vintage rolling stock, it has a period feel to it, and seems rather like what you would find in a model railway magazine of the 1950s.

For those who are interested, the camera was a Leica IIIa, the lens was an uncoated f3.5 5cm Elmar, and a Leica close up attachment was fitted between the lens and the camera body. The haziness (or call it bokeh, if you prefer) in the photograph to me adds a certain character and period charm and was mainly due to the low filtered light in the room (no flash was used) and the lack of coating on the lens (it dates back to 1934, before lens coatings were in general use on 35mm camera lenses).