This very complex machine has one job — to flip a water bottle. Built entirely out of K'NEX, YouTuber Thibault Art has created something that gets the viral water bottle flipping challenge right.

An exemplary display of the latter is The Citadel. Over the course of three years, redditor [Shadowman39] pieced together this monstrous K’nex structure. With over 17 different paths(!), ...

which featured K'Nex. "Working as a team to help you make stuff, especially when the machine works, it's just kind of rewarding, you know, seeing all of your work, your hard work, because it puts ...

Instructables user [birdycrazy] built a winding rig from a PVC pipe and a bunch of K’Nex. He had recently started a Tesla coil project and needed an efficient way to wind the secondary coil.