My dad worked on the railways for his whole life, which, as a kid, gave me very cheap (almost free) railway travel, so while most of my mates spent summer holidays kicking a football against a wall, I spent the day in Brighton, or Southampton, or Bristol...etc.
As a teenager I collected N gauge railways, and when I built this house 20 years ago I got all my old stuff out of boxes, added to it and built this (vid attached).
All now back in boxes (room needed for other things), but it had a good few years use. Very therapeutic and quite mesmeric to watch.