I have discovered a way to create copies of movie posters to make little station platform signs. It is probably some sort of copyright infringement to post images of what I'm talking about, and definitely not a thing one should do to sell them commercially, but for private entertainment in one's own basement, it's probably OK. If Wikipedia can display them on their website, I doubt if the copyright cops will bang on your door.
Go to Wikipedia, type in a movie title and there will be an advertising poster from the original release. It can be copy-n-pasted into a word document, and printed for your own little train world on suitable paper.
