My school had an old pin which they used to demonstrate physics stuff  - coils and electromotive forces and all that. It never seemed to be in full working order though (perhaps that was intentional, to stop us playing on it) but I always looked in awe at the teacher who new how to fix it when a flipper stopped working or something like that.  It gave me a taste for pinball and for physics though.

Anyway, I figured that I could never own one because it would be too hard to fix without a teacher on hand. Turns out I was wrong on both counts.