A gimmicky gadget that might work! Look at how well reflectors on bicycle pedals show up, and flashing bicycle lights (I'm a bit dubious about the front or headlight flashing) plus of course police, ambulances, fire engines and hazard light.
I have to confess I'm a bit paranoid about being seen following an accident I had many years ago back in the days when people drove on sidelights. It was tipping down with rain and the road was soaking. In amongst all the reflected lights I just didn't see this car - had the idiot been driving on dipped lights I would have seen him
. My beloved Mini, my first car, had to be consigned to the scrapyard.