rinky dink (i think these words are hopelessly co-dependent. hard to think of any thing rinky, except a dink.. not that i know what a dink is.. )

There is a short train (only 2 cars) that goes from the Princeton U campus to an AMTRAK station in the next town ( a 10-minute ride, I think) that has been lovingly named the "dinky" by the students there.

I clipped an article about it and I am sure there was an explanation for the word dinky in it but I am afraid it will take a month's spring cleaning for me to retrieve that article.
I hope some one comes up with something quicker than that.