Driving along a packed freeway today, I saw a big brass cap sitting in the lane to my left, just on the other side of the line. Luckily the cars in front of me, and to my left missed it, but as I watched in my rear view mirror, I saw an Audi drive over it, and the cap shoot out like a rocket across three lanes of traffic. It reached a max height of about 5 feet, just high enough to pummel a mid size sedan driver's face. I saw a Cadillac swerve, but luckily no one got hit, and it made it onto the right hand shoulder. Another quarter mile down the road I passed the porta potty hose that the cap belonged to, laying in a different lane. So, if someone had got hit with it, not only would it have messed them up bad, it would have been with a porta potty hose cap!
So, what's some of the worst roadway debris you've ever seen?