Model Railroading: How to make realistic mountain rock faces

I talked with some friends of mine this past week who are doing their own model railroading, and one of them told me an interesting technique for making realistic rock faces.  Since he is from West Virginia, most of the exposed rock faces he sees are the angled sedimentary rock layers, especially along the major roads where the construction crews had to dig into the mountain to lay a steady grade.  His trick to reproduce this effect on his train layout was discovered just over his head: ceiling tiles.

Model Railroading: Adventures in self-inflicted pain

Ever since I was a young kid, back when my older brother enjoyed having me share a room with him so he could hit me with his pillow in the middle of the night, I have always been a model railroad fanatic.  Unfortunately, most of the places where I lived we did not have room for a train table.  Now that decades have passed and I live in a house large enough for a train table once again, I am once again able to enjoy the pleasure and sweet pain of planning and building a railroad layout.