In 2006 a new miniature scale of model trains were introduced, the T gauge. I believe we can go even smaller! This is a complete train set that is the size of a book, featuring a motorized train that has variable speed and the ability to switch tracks on demand.
The locomotive is propelled by a magnet attached to an on-rails motor in the base. This system is a lot like those mechanical PONG tables which debuted a few years ago. The nose of the train has the metal needed to be pulled by the magnet below.
The rails system is something you’d find in a 3D printer, image scanner, or even an Etch-A-Sketch. It would guide the tiny train along its route that is stored in an onboard computer. It would be nice to swap out the track for different layouts (these could be printed on cardboard).
This desk toy would feature dedicated controls for the track switches, and a big dial for the speed. When this device is powered off, the train is automatically diverted to a side rail where it parks. The design above is sparse but the layout could be populated with buildings, trees, vehicles, and so forth. Lights and sounds are also possible.
There are drawbacks! Only one functioning train is possible, the train length would need to be short, and the terrain would need to be flat (you can add tunnels, but no bridges over rivers for example). And lastly if the motor is loud this concept wouldn’t be worthwhile, this thing needs to be quiet!
In the meantime you can buy these neat tiny trains but they feature basic oval tracks.