I added a Miniatronics "Rear End Warning Flasher" on a box car, to be used on our micromodule layouts, when running a more modern train. I replaced the supplied LED, which was large for N scale, with a surfacemount red LED. The power leads go to the trucks, which have homemade axle wipers to pick up power from the Fox Valley Models steel wheelsets.

(I noticed that through some trick of compression and frame rates, that the train looks like it's moving erratically; it's not but I was having trouble uploading the 14MB original file last night, so I had to compress it.)