indirect communication at 50 mph

'driving back last weekend there was a wonderful speech bubble on a motorway signboard. It seemed to be malfunctioning, the pixel effect much larger than usual, and in 3 shades against the black background the led lights formed a rectangle in grey, then a single grey green light in the bottom left outside the rectangle and a single bright orange light within the rectangle itself.'

Image and words from J the other morning. 
It's lovely to know that people think about what you're doing from time to time.
Thank you.