if you're into this kind of thing, there's a pretty good 8and now, se,i.famous) scifi book by Adrian Tchiakowsky, Children of Time, that tells the story of a spider civilization that evolved to form cities and scientists and all that, and they use domesticated ant colonies as analog computers. Also, in Liu's Three Body Problem, a rather central story element is that the civilization on trisolaris employs literal armies to make a circuit board layout to calculate with it. Visualized rather impressively in the (real) show