The Ra is a fascinating and innovative digital music instrument and optical media reader, developed by Dmitry Morozov, that uses a special laser to scan uneven surfaces of pyrite suns and produces high-quality synthesized sounds.
This device makes use of a Raspberry Pi and Arduino Nano as its heart and brain. It is equipped with a digital sound processor, stepper and servo motors. It also features a 3-volt mono sound system and a custom laser pickup/reader, and if you look close you'll notice that there's a nifty control board that runs down one of the edges of the triangular base. An array of switches and knobs allow you to introduce envelope filters and modulators into your musical creations.
Ultimately, the Ra is both a digital musical instrument and a scientific contraption of some note.