About half the cab of a big rig hanging over the lane I was driving in.

880 North in California, early 2000’s around 2AM. South of Oakland driving in the fast lane, it was foggy and I was going a bit to fast. Then I started noticing a whole bunch of weird stuff all at once; 20+ cars pulled over on the shoulder with a cop car in front of them, small rocks? all over the road that rapidly became chunks of concrete a few inches in on a side, a whole ass sideways car — at this point I’m slowing and pulling out of the fast lane, as I finish the lane change I look back ahead just in time to see the cab of the big rig dangling over the fast lane from the other side of the freeway. It just appears out of the fog, I’m not sure my car would have cleared it if I had still been in the left lane. It had punched right through the concrete median (the rocks all over the freeway were debris from the collision). The southbound side of 880 is higher there, so it was at least 4-6 feet above the ground on my side.

Bonus: A different big rig with a 25 foot aluminum ladder stuck on one of the trailers feet. It was shooting a roster tail of white sparks another 15 feet, skipping around and making quite a bit of noise. Got a good look as I passed and it had clearly been hooked for a while, it was ground down a few inches where it was making contact.