Canjo

This is a Canjo. It's a coffee can with a stick and some strings stuck through/to it. It's fretted like a dulcimer - "just intonation" I think (?) - basically a major scale + a flat 7th.

Because it's missing all the chromatic frets, tuning a second string to a different note or playing to a song in a relative minor makes your guitar player fingers make unusual note choices.

Here's some music featuring it:

The Moon is a Cell (26 min)