The lawyer and entrepreneur even touted it over the holidays as an ideal stocking stuffer.

), who have all posted videos of themselves playing the game.

Boxbollen says just a few minutes a day will help improve reflexes, agility, coordination and movement.

rfk jr. boxbollen

YouTube/Boxbollen

An accompanying app lets you track your scores and progress.

you might even compete with other Boxbollen users from around the world.