I was thinking about some carefully-sculpted "chrome mudflaps" or something on the back of my small car, up near the window. Obviously they wouldn't do much for

I was thinking about some carefully-sculpted "chrome mudflaps" or something on the back of my small car, up near the window. Obviously they wouldn't do much for mud, but if they're purely passive, I think they'd still be legal. If someone's following at an appropriate distance, no issue, but if they get close enough for their lights to point at my window, they'll be eating their own glare.