Currently listening to the audio book of Dune, which led me to go look up who played Gurney Halleck in the movie (I had somehow forgotten it was Patrick Stewart! Who looks exactly the same 30 years ago as he does now!).
Which led me to this kickass little scene that never made it into the theatrical version, of Gurney playing his Balliset for the entertainment of some of the other major characters (if I have this right, as they go around the room in order:; Liet Kynes who is really into it, Dr Yueh, Thufir Hawat, Duke Leto and Paul Atreides.)
Turns out, the instrument he's playing is in fact real, and the composition is too: It's a Chapman stick with a weird swirly thing stuck on it for visuals. And the composition is called "Back Yard" and is actually played by the dude who invented the Chapman stick.
Anyway, that got me wandering YT for more of this fascinating instrument, including a guy playing duelling banjos against himself at the same time on the same instrument. It's really pretty neat.
But if you'd like to hear more (and see how it's really played, since Patrick Stewart is faking it), then there's this really lovely version of "While My Guitar Gently Sleeps" too.
Also, yes, I am an unashamed fan of the Lynch movie. Loved it as a 13 year old fresh of my first reading of the books, love it just as much now, rather a few years and re-readings later :)