(Except trains, that is.)
Something useless!
That has been on my build list for at least 2 years now. Maybe someday I will actually get around to making it.
LOL!
You can buy kits these days.
This one is a box from Hobby Lobby. I sawed the lid in two, then stained and varnished it. Inside is a miniature servo of the 1 or 2 dollar variety, a switch, 3 AAA cells, an attiny10 micro and a mosfet to turn off the servo when it’s not doing anything.
If I had one, I would put at the railroad and watch expressions!
This is pretty neat and have seen some variations in the past. Looks like I will be visiting the local Hobby Lobby. Thanks to you Tom. 
Hours of fun!
At least till the batteries run down 