Rube Goldberg Machine

A Rube Goldberg machine is a contraption that achieves a simple task, often moving a ball from one place to another, through very complicated means.

This is a contrived example of emergence. Typically, emergent behavior is not designed and arrives spontaneously, while this is not the case it still illustrates the idea -- many simple things coming together exhibiting complex behavior.

For more information on Rube Goldberg Machine's see Wikipedia's Page on the Subject

For a particularly cool example see this video of a Japanese Rube Goldberg Machine cooking ramen: