I hate to say it, but I don't get what the big deal is.
Air molecules have mass, and they have velocity (and by implication, acceleration). Therefore, they have force (F=ma)
Left unhindered, that force is acting in every which way (sometimes the ball goes up, sometimes it goes down).
But if you have a situation where you can actively select a path the force can act upon (that is, barriers preventing the ball from travelling except in a certain direction), then of course the ball will travel in that direction, eventually.
This is sort of like lochs, only a lot smaller. We block the river on one side, let it fill up, then release the block so the water can only go in one direction, repeat.
How is this revolutionary, or breaking the 2nd law of thermodynamics?