For his birthday, I bought my husband a music box, but not just any music box.
This one lets you compose and use your own music! Did I mention my husband plays multiple instruments, by ear?
I thought this would be right up his alley.
Plus, all the parts are replaceable, just in case.
The box:

The inside:

You feed the music through the slots and turn the handle to play it, which slowly pulls the music through.
The paper:

Along with two pairs of the hole punches used:

A variation of ‘Happy Birthday!’ came on a sheet, and he punched it out so it would play. When it’s done, it looks like this:

And OF COURSE I got him a ridiculous amount of paper.

So now he can make as much music as he wants!
I love finding presents for people that they don’t know they want yet. *smile*