GPS. In the 80s, I learned how to navigate by taking the bearing of landmarks. It took some time and gave you only a general idea where you were.
When I got my first GPS device in the late 90s, it was breathtaking. And at that time, the accuracy was still degraded for civilians.
The idea that a navigation device can show on which side of the road you are on - in real time! -feels like magic.
Gibts in der Schweiz schon lange. Rasen -> Straftat -> Einziehung des Tatwerkzeugs.