Playing with trains.

[Robert Hofstra]

What fun you can have with a 95 cent app on your Mac.
All in all 10 minutes work.
The original.

left left

right right

 

[Lemaildetom]

Excellent! I have no idea what kind of sorcery you used for doing this!

 

[AJQS]

Clever little app, the last image works pretty well too, love the emptiness!