Now Boarding on Track #2: The Broadway Limited:
I always secretly wanted the Postwar Lionel Operating Dispatch Board as a kid, and got it for cheap as an adult at a train show.
Got it home, didn't work. Seemed hopeless at first. Opened it up and dead moths fell out. I tinkered with it, sprayed a little WD40 in the mechanism and Eureka, it has worked like a charm ever since.