... leading to the invention of the old cat of nine tails, nine pieces of rope hanging from a wooden crossarm over the track, attached to a trackside pole. Each rope had a knot tied on the end, to weight it. If you were on top of a car, walking away from the locomotive and felt the ropes and knots brush the back of your head, you knew it was time to hit the deck. Bridge or low tunnel coming up right away! All of them could clear a man in a prone position.
A five rope version survived in Winston-Salem up until about 20 years ago.
As for camp cars, they still exist today, though they are more likely to be mobile homes on flats rather than the repurposed passenger cars of previous recent decades. Downtown Greensboro, NC is a common place to find them parked when not in use, near the Elm Street crossing.