Crank it and watch the duck waddle. Set it on a desk or windowsill and turn the ring crank set into its side. The eccentric cam rocks the belly and swings the paired hips into a duck waddle while the clip beak snaps open and shut. Pop off the roller skates and it waddles in place instead of rolling. A quiet fidget for a coworker or a kid's shelf.

How it moves. Turn the ring crank set in its side and an eccentric cam takes over: it rocks the belly, swings the paired hips left and right, and snaps the clip beak open and shut in time with the waddle. Let go and the duck settles back down, ready for another turn.

Fit and finish. Made in PETG with a fine layer finish, this palm-size duck stands 5.2 inches tall and weighs 0.3 pounds. The square eye windows key flush into the head shell without glue, the beak hinge shows a crisp printed seam, and the belly panel rocks smoothly against the body with no rattle.

Skates snap off and on. Two roller skates clip under the feet and hold the duck captive on its wheels for a smooth desk roll; pop them off and the same duck waddles in place on its bare feet instead. Swap between the two without tools, then set it back down between turns of the crank.