Quantity   Component name
1 × BeagleBone Black
1 × USB projector supported by libam7xxx I already had one, for a new build a HDMI projector may be used too.
1 × USB Y-cable needed for the USB projector to suppy some more current to it
1 × USB power bank
2 × latching Hall effect sensor
1 × Magnetic spheres like the ones from the Tetramag toy, they are used as a magnet ring
6 × Momentary push button