I’ve used Kalas bowls and plates to construct Quiz-buzzers for my classroom. With a bit of wood and buttons from an old keyboard. The pictures should tell nearly enough. I connected it all to a Velleman MK133 quiz-kit (well, I made my own based on their schematic).
– Kalas bowl and plate
– piece of wood 12x12cm
– piece of broomstick (about 3cm)
– piece of foam insulation
– Wire (I used old UTP patchcables)
Drill holes in the center of the plate and wood. Drill some more holes (see pictures, can’t really describe it in words…). Connect the LED, screw the broomstick to the piece of wood, glue the button on top. Glue the foam to the Kalas bowl and you are done!