B2/S13
and related rules have a simple replicator
that acts with period three on a one-dimensional 3-unit grid:
Jason Summers discovered 3c/3 spaceship based on this
replicator:
and a similar one in the related rule
B25/S13:
Replicators --
Cellular Automata --
D. Eppstein --
UCI Inf. & Comp. Sci.
