I once passed a truck going in the opposite direction, and a rock came off and smashed my LHS window. Luckily I was sitting the right (advantage: RHD!) but still got glass in my hair, ear, <img src="/forums/images/graemlins/scared.gif" alt="" /> and coffee.

I never did find the rock. It didn't come into my Paj. Is it possible that a projectile hit it, either off of a passing vehicle, or from someone's hand? Wouldn't necessarily be in camera range...?

1991 HZJ77, 1999 KZJ90, 1999 UZJ100, 1992 M101CDN2
https://www.thegearheadproject.com/category/jdm-journeys/