I designed this advertisement for the HTC One competition recently.
In so doing, I thought up today’s invention.
Given the effort involved in all of that pasting up adverts on hoardings, why not instead project the ads, using existing streetlights?
Advertisers could pay for each light in front of a hoarding to be equipped with a computer-controlled mini projector, powered from the light’s own electricity supply.
This would allow each hoarding to show a variety of different ads at different times, eg school run or afternoon drive-time. These projected ads could be films.
The films could even be made silent, but with a soundtrack that people could hear via the radio as they drove or walked by.