Wikipedia: Incompatible_Timesharing_System
Computer operating system built by MIT AI Lab – notable for interesting principles of openness, collaborative approach, development of hacker culture. For example; adding a available-to-anybody system command to crash the computer to help take away the temptation of hackers trying to find a way to crash the system. Led to emerging early programming hacker culture and principles, and ideas around free and open source software.
Zen and the art of Radiotelegraphy
Ebook by ham operator Carlo Consoli, IK0YGJ. I think this is the best description of why and how to learn to use Morse Code for telegraph and radio communications. Suggests meditation before periods of practice.
PiDP-8/I – Hardware emulation of digital PDP-8 including front panel
Includes a front panel with proper switches and blinking lights.