MEOWSER is a (M)ineral (E)lement Br(owser): a wooden display cabinet containing rocks and mineral samples with LED lighting controlled from a laptop computer. The laptop can display either the periodic table or a layout of the cabinets. When the user mouses over elements or minerals the appropriate lights in the wooden cabinet light up. An Arduino microcontroller serves as the computer – LED interface.
Here’s the video explaining how it works: