The Gosper Glider Gun. Simple, beautiful, complex, poetic, mezmerising.
The Gosper glider gun is the first known gun, and indeed the first known finite pattern with unbounded growth, found by Bill Gosper in November 1970. It consists of two queen bee shuttlesstabilized by two blocks. It is the smallest known gun, and, as it can be constructed using only eight gliders, it has the smallest known glider synthesis of any gun. It can be destroyed completely by five gliders.