This is a board designed for LED Chess!
This two-piece board was designed in Inventor to be 3D printed, due to fabrication constraints while working at home. A 1 meter LED strip (WS2812B or SK6812) fits between the ridges in the base, and the oval shaped holes on the right side are for routing the input and output wires, reducing stress on the strip itself.
Atop this board sits a square sheet of sanded acrylic, which diffuses the light, spreading out the light from each of the LEDs. I likely would have designed the whole board out of acrylic if I had easier access to a laser cutter and other fast fabrication techniques, but this model is more accessible for anyone who wants to try it out on their own.