Best Drivetrain

[AmoryG]

That's a really neat drivetrain. It's interesting because this is much different from all of my ideas I've had so far. I turned my thoughts away from doing it like this because I always imagined the ball would slip around or would be too smooth to control. It's nice to see an effective way to use balls instead of wheels.

But are there any designs which are effective using only balls and no wheels? That's what I'm going for.