living organisms are very complicated aggregations of elementary parts, and by any reasonable theory of probability or thermodynamics highly improbable. that they should occur in the world at all is a miracle of the first magnitude; the only thing which removes, or mitigates, this miracle is that they reproduce themselves. therefore, if by any peculiar accident there should ever be one of them, from there on the rules of probability do not apply, and there will be many of them, at least if the milieu is reasonable. -john von neumann, from his theory of self-reproducing automata. the study of artificial self-replicating structures has been taking place now for about half a century. penrose’s wooden tiles, greg chirikjian’s lego robot, cellular automata, etc. now we can add to that list hod lipson’s molecubes. check out the videos, and read the faq for some interesting stuff. also here’s a short article from new scientist.