Today’s invention is one of those teletext type scrolling displays which you see on the fronts of some buses.
This would be extended vertically and lengthwise, as indicated, to include information beyond the normal destination name eg adverts/news.
The idea is that, as the bus turns, so the message scrolls relative to the bus -so as to appear constantly at the same angle to a stationary observer.
This would add some novelty but also increase the viewing time which any individual could apply to a given piece of information.