Tangentially related, I highly recommend the Steven Levy book Artificial Life. It's pretty dated now, but it's still a fantastic read. I couldn't put it down.
Strongly seconded. Reading "Artificial Life" in my teens was a formative experience for me. Reading about Tierra[1], in particular (and being an assembler program who also played "Core War"), filled me with wild enthusiasm. I even went so far as to try implementing something similar on my own (albeit I never did get it into a finished state).
re: this article - I was surprised to see somebody thinking about modeling evolution in computers all the way back in the 1950's.
