How about cellular automata simulating (spoiler) complex life forms in many dimensions, implemented in large polysaccharide constructions? :) (Greg Egan's "Wang's Carpets", later incorporated as a chapter into his "Diaspora".) http://bookre.org/reader?file=222997&pg=1 (http://archive.is/ocAgN)
I always found that to be a little sad. iirc, the Carpets in the story are completely deterministic - while there is life there, it will always unambiguously lack free will. (Though I suppose they'll never know it.)
That was the Horta in the original series. It finally said "No kill I" after Spock mind melded with it.