If it moves, it breaks
When I think of examples of mechanisms my first thought is a system that moves recreating the behaviour and structures we see in nature.
An example of this is the work by kinetic artist Reuben Margolin. He designed a simple mechanism based on the mathematical qualities of caterpillars crawl, which uses strings connected to different sections to create motion applying a circular force.
He has implemented this same mechanism in many of his works, creating three dimensional structures and also using different materials.
I specially like this piece where he attaches the strings mechanism to a human body to create a life performance:
In the video below, he explains how he came up with the idea. In minute 4:30 he shows a preliminary version that fails because it doesn’t accomplish the fluid movement he was looking for. Instead, it moves a Little and then it gets stuck. I’m pretty sure one of this early versions broke at some point.