You know how you should always stand beside the blade and not behind it? And when you make a cut where there will be a little offcut, you set it up so it's on the free side of the blade?
That saved me from injury the other night. I made one mistake: I didn't use a zero clearance insert on the cut, a 45 degree angle cut in plywood. The thin spear fell slightly between the blade and insert and was picked up by the blade and thrown backwards. It was there and then it wasn't!
I found the spear had punched its way through a air fitting package (not the fitting, just the thin plastic package) and stopped about 10" after it exited the other side.
Puckdropper