Just Because It's Neat
A guy in a lab was playing with Quantum Dots
and has come up with an energy saving way of creating light.
While the nano-crystals [we are talking 100 atoms and less] are known to produce light, he discovered a way of making them produce white light that can be used to increase the output of light emitting diodes [LEDs] with no increase in power consumption.
If you created a film or spray with the dots you could have a surface that would generate its own light in the presence of a lesser source. For example, if you coated the inside of a tunnel, your headlights could cause the entire tunnel to glow with a much brighter light than your headlights alone could produce.