[oakenshield]

I've read a few bits and they're all great one way or the other, primarily because chapters on specific projects are written by their primary authors. A couple of good ones

Nginx: http://www.aosabook.org/en/nginx.html LLVM: http://www.aosabook.org/en/llvm.html Sendmail: http://www.aosabook.org/en/sendmail.html

Although this means there's no consistent style across chapters, it's really something else to hear about the architectural and design decisions that the author made, and how they look back at those decisions now (esp. in the Sendmail article).