Found on https://www.rsaconference.com/library/Blog/bens-book-of-the-month-review-of-computer-security-and-the-internet, a review of Paul C. van Oorschot's "Computer Security and the Internet: Tools and Jewels from Malware to Bitcoin".
https://www.amazon.com/Vulnerable-System-Information-Security-Computer/dp/1501758942/ref=monarch_sidesheet_title

The system provides a dedicated package EL (EMACS-LISP), and some definitions.
Found on the Emacs Wiki https://www.cliki.net/el
See also https://framagit.org/akater/lisp-primes-for-trickontology

Found on the Irreal blog https://irreal.org/blog/?p=12924
See also https://joshblais.com/posts/whats-on-my-phone-2025/ and https://joshblais.com/posts/gnu-stow-is-the-way-to-manage-dotfiles/, https://joshblais.com/posts/zen-browser/, https://joshblais.com/posts/how-to-integrate-org-mode-and-google-calendar/

Found on Lars Ingebritsen's blog https://lars.ingebrigtsen.no/2023/07/19/raspberries-screens/

Found on the MoHP forum https://www.hpmuseum.org/forum/thread-23365-post-202412.html#pid202412
See also the interesting http://www.luschny.de/math/zeta/The-Bernoulli-Manifesto.html which convinced Donald Knuth to correct the definition of the Bernoulli number B_1 in his book Concrete Mathematics.
The index http://www.luschny.de/math/index.htm gives a good overview (in german).

Found on the Spritely institute forum https://community.spritely.institute/t/step-one-identity/615/3

Documentation for the S7 scheme interpreter, which can be found on https://ccrma.stanford.edu/software/snd/snd/s7.html

I shall change my Emacs settings to use setopt instead of setq, but consider the places where Emacs versions older than 29 are used.
See https://www.reddit.com/r/emacs/comments/178em7u/why_was_setopt_introduced_in_emacs_29/?rdt=39547 for some background information.
So conditionally defining setopt to customize-set-variable on older Emacsen might be a way to unify my setup files.

Branch of GNU ed maintained by its original author Andrew L. Moore.
Found via https://lists.gnu.org/archive/html/bug-ed/2025-01/msg00003.html

Found via Sacha Chua's blog https://sachachua.com/blog/2025/03/2025-03-10-emacs-news/
The site (in romanian) can be seen on https://parsec.ro/. See also Josep Bigorra's blog https://jointhefreeworld.org/ and Marcin Borkowski's
https://mbork.pl/2023-07-22_Org_Clive_-_a_new_Org-mode-based_blogging_engine