about 25 years ago i was a roofer working on a building next to the hard rock cafe,i was cutting a slate on a parapit wall when the slate decided to launch itself off the building and proceeded to aim for a moving taxi,thwack straight into the said vehicles roof sticking out like an ice cream cornet.me and my partner sloped off for the rest of the day and pretended as if nothing happened we were never questioned and never mentioned it to any one except our mates.