This ping pong ball rainbow will look good just about anywhere in your house, including a children's space, the front door, or the living room. First, choose a color palette for the rainbow ...

[Jacob] has put a slightly new twist on the levitating ball trick with his ping-pong ball levitation machine. We’ve all seen magnetic levitation systems before. Here on Hackaday, [Caleb] built ...

How Opal Forms Opal is known for its unique display of flashing rainbow colors called play-of-color ... microscopic spheres stacked in a grid-like pattern—like layers of Ping-Pong balls in a box. As ...