I've probably mentioned this before, but a co-worker back in the early 70's told me about the time he was ripping a narrow strip of paneling on his RAS when it kicked back - and the strip of paneling flew across his basement and stuck into the block wall. He was trying to educate me as I was getting ready to buy my first saw - made a big impression because when I recently sold the RAS it had never been used for ripping in the over 40 years that I used it.
I have however been hit by a piece of plastic laminate - I would duct tape a piece of laminate to the TS table over the blade slot, move the fence over the top and raise the blade to make a zero-clearance insert when ripping self-edge out of a sheet of laminate. Done it a million times, but one time the tape didn't hold - old tape/dust on the top, whatever - and the spinning blade caught the underside of the laminate and spun the corner right into me. I can confirm both that it really, really hurts and that the bruise seems to take forever to heal. I have since bought a metal "angle guide" that fits under the fence and provides a vertical surface to prevent the laminate from slipping under the main fence.