Build a Better Monster: Morality, Machine Learning, and Mass Surveillance, by Maciej Cegłowski. Required reading.
LambdaDelta is an emulator of the LMI Lambda Lisp Machine. (If you are looking for the ROMs, look here.)
What Is Digital Humanism?, by Tim Carmody.
A Source Book in APL, Papers by Adin D. Falkoff and Kenneth E. Iverson, with an introduction by Eugene E. McDonnell. Recommended reading.
Category Theory, Syntactically, a very non-traditional introduction to the ideas behind category theory.
A Mind Is Born, impressive 256 byte(!) C64 demo by Linus Akesson.
Starfriends is an inclusive social network/dating site. “It doesn’t ask for your gender, and never will. Instead, you can add to your profile an unlimited amount of tags to describe yourself, the persons you’d like to meet and the activities you might want to share with them.”