In Naruto, the Rasengan is a swirling chakra ball that can be held and thrown by ninja. This looks like the Rasengan but for real.
https://twitter.com/embed/status/1054001455940730881
Spotted at this year’s Hack Day in Japan, this project is called micRokuro and was created by Yoshimasa Kato.
https://twitter.com/embed/status/1069799655116926976
It works very well with Naruto music!
https://twitter.com/embed/status/1069830632841207809
Here is a better look at the project.