Found on Tony Finch's link log https://dotat.at/:/
There is also a nice introduction to TCP sockets at https://woozle.org/papers/sockets.html

Boot an UEFI machine over the network using the Plan 9 protocol.

Gemini is a new, collaboratively designed internet protocol, which explores the space inbetween gopher and the web, striving to address (perceived) limitations of one while avoiding the (undeniable) pitfalls of the other.

Found via Alex Schroeder's page https://alexschroeder.ch/wiki/Gemini

NomadBSD is a persistent live system for USB flash drives, based on FreeBSD®. Together with automatic hardware detection and setup, it is configured to be used as a desktop system that works out of the box, but can also be used for data recovery, for educational purposes, or to test FreeBSD®'s hardware compatibility.

Found via https://pirsquared.org/blog/, where I followed a link to the sad, but interesting story of the Xfree fork to X.org.
http://asterisk.dynevor.org/xfree-forked.html
I have not read
https://matthew-brett.github.io/curious-git/
yet, but it sounds interesting.

LambdaNative is an open-source (BSD licensed) cross-platform development environment written in Scheme (Gambit-C), supporting Android, iOS, BlackBerry 10, OS X, Linux, Windows, OpenBSD, and NetBSD. Some cross-compiler support for Raspberry Pi (Carlson-Minot) and OpenWrt (Sitara) also exists. See also https://www.lambdanative.org/

This package provides a library and a command-line tool named wormhole, which makes it possible to get arbitrary-sized files and directories (or short pieces of text) from one computer to another. The two endpoints are identified by using identical “wormhole codes”: in general, the sending machine generates and displays the code, which must then be typed into the receiving machine.

The codes are short and human-pronounceable, using a phonetically-distinct wordlist. The receiving side offers tab-completion on the codewords, so usually only a few characters must be typed. Wormhole codes are single-use and do not need to be memorized.

Open-source hard- and software for two-factor authentication.
I need to test them and want to understand the differences between versions 1 and 2. The articles
https://solokeys.com/blogs/news/trussed-announcement and
https://github.com/trussed-dev/trussed-totp-pc-tutorial look interesting.

Delta provides language syntax-highlighting, within-line insertion/deletion detection, and restructured diff output for git on the command line.
Found via https://tecosaur.github.io/emacs-config/config.html
There are other programs using the name delta, for example
https://guix.gnu.org/packages/delta-2006.08.03/
"Delta assists you in minimizing "interesting" files subject to a test of their interestingness."

Gqrx is an open source software defined radio receiver (SDR) powered by the GNU Radio and the Qt graphical toolkit.