Here’s one I came across on a kenjutsu dojo’s website once - good music for physical training (or war preparations, as the case may be):
Also, the traditional song “Sakura Sakura”, here performed on the koto:
First time I heard it was in vocals-only version in this 3D motion capture tech demo called “Kara”: https://www.youtube.com/watch?v=j-pF56-ZYkY