Glo Nightlight

Glo Nightlights are marketed for kids. However I want one. Still with the concept of tangible/visual energy, these lights are exact representations of the idea. They change colour and have a goofy low-energy LED base with 9 volt power adapter. The balls glow for 30mins off the charger and dont have electronics in them...so perfectly safe for children. How they work, I still have no idea.
You can buy it here: booninc

This guy, David Di Franco, has a fun vid about unpacking and trying out the Glo Nightlight. And good on him for buying a kid's lamp.