It figures that a man impassioned by light would work in photoluminescent products. These are products manufactured by my company, Safe Glow Corp http://www.safeglow.com)
These are door knob rings of various shapes and sizes, path markers for adhering on sidewalks, K rails and crosswalks, and key ring markers which help women find their keys in their purses. They all absorb light and glow for about 14 to 16 hours when lighting is removed. It's fun to play with light!