Given the enormous complexity of modern technology (100+ KLOC software projects, 1+ billion transistor CPUs, etc.) I view security failures to be an inevitability: the attack surface is rich for exploitation by enemies, and bugs and errors constantly emerge due to both man and machine. That said, I do not think it unwise to consider it a prerequisite for the most paranoid-level technologies that they be easily understandable and scrutinisable by individual people. Hence, I have an interest in pen-and-paper ciphers, simple wireless communications systems for Morse, voice, and data, and simple computers. Is this something other people think is a sensible or important line of inquiry? Do these technologies and the people using them exist? Are there movements advocating this approach? Thank you.