Computer scientists at Kobe University in Japan have built a computer that draws inspiration from the swarming behavior of soldier crabs.

The computer is based on theories from the early 1980s that studies how it could be possible to build a computer out of billiard balls. Proposed by Edward Fredkin and Tommaso Toffoli, the mechanical computer was based on Newtonian dynamics and relied on the motion of billiard balls in an idealized, friction-free environment instead of electronic signals like a conventional computer.

Simple systems, complex results…welcome to the natural world. 

Computer Built Using Swarms Of Soldier Crabs | Wired Enterprise | Wired.com
http://m.wired.com/wiredenterprise/2012/04/soldier-crabs/