Ben Kokes started out by designing and developing a circuit that would be able to power up the ring inductively. In the end, he used a coil of wire wound around kaplon tape as the inductor and a small SMD capacitor to power up three tiny ultra-bright LEDs.
Thirst Aid is a reusable hydration pack that looks like a saline drip pouch, but you can fill it with your favourite energy drink. It stands upu like a bottle when full and can be folded or rolled when empty. Not suitable for hot drinks.
The paper LED torch light by Japanese designer Kazuhiro Yamanaka is made exclusively using a cut-out piece of paper and a battery operated LED. The LED attachment is automatically powered via two thin hidden switches. As soon as the volume becomes flat again, the light shuts off.