The century eater is a 20-cell still life that functions as an eater for the active reaction produced by any century relative. The most well-known use is to replace a four-object constellation in Paul Callahan's bistable switch, as shown below. In September 2014 Josh Ball showed that a variant of this still life has a relatively inexpensive slow glider construction recipe.
At t=256 the active reaction produces an eight-cell pattern sharing the same grandchild as a century. The century eater at the top of the pattern catalyzes this pattern produce a clean spark.
- 20.32670 at Heinrich Koenig's Game of Life Object Catalogs