maybe not the worst, but I have these two stories:
This one lil' gaper two seasons ago was bombing the black at my hill with moguls, the moguls don't fill the whole hill - they're man made. (midwest) and i don't know if he even saw them or not but just runs right into the biggest mogul with a ton of speed and BAM he dub ejects and lands chest first on another mogul. that must've at least broken two ribs. and he kept rolling. and rolling. to the bottom of the hill almost to the chairlift. wasn't sure if I shoulda laughed or been worried.
second story, same run. same situation, kinda. It was a ski club night and some i believe some dumbass kid and his stupid friends decided to bomb that run, gaper - tuck. Dumbass (we'll call him that) is doing a steady bomb and clearly doesn't see the moguls. catches his tips on the mogul and front flips to head on another. on his stomach he slides in between the moguls and is still. knocked unconscious. dumbass' friends just ignored him. after three lift rides someone sees him, not even a ski patroller (that was the 5th ride). word is, he only broke his thumb. no concussion, or anything!
sorry for the long post!