This was my entry for a competition on GrabCAD.
In some favelas, where windows are rare, a clever trick to get daylight into your home is to fill a drinks bottle with water and fix it so half of the bottle is above the roof.
This gathers the light and distributes it inside. To take this further EN3D thought to add a solar panel, batteries & LEDs to turn it into a nightlight too. Reducing the need to burn so much fuel and reusing at least 1 plastic bottle. They wanted a design that could be 3D printed locally.