Interesting software, such as
unifdef selectively removes C preprocessor conditionals. My version of this program now shipped by all the BSDs (including Mac OS X) and is used by the Linux kernel build system.
regpg safely stores server secrets using gpg, so you can keep them in version control.
picoro - tiny coroutine implementations in pure C. I wrote an accompanying article, coroutines in 20 lines of standard C.
Counting the days - tiny routines for converting Gregorian dates into linear counts, like Julian day numbers or Unix time_t. The date of the count - a small routine for converting linear day counts into Gregorian dates.
https://dotat.at/@/2016-04-22-synergy-vs-xmodmap-fight.html Why you can't use xmodmap to change how Synergy handles modifier keys
https://dotat.at/@/2023-05-26-whence-time.html Where does my computer get the time from?
https://dotat.at/@/2023-08-04-unix69.html a neat keyboard map
https://dotat.at/@/2024-01-29-four-point-egg.html construct an egg shape with straightedge and compass
His log of links, https://dotat.at/:/ which I found on the TUHS mailing list is also worth reading. He explains a bit about this log on http://dotat.at/.

How to choose and configure keyboards for efficient typing. Found Wed Dec 21 18:38:57 2016, rediscovered Tue Aug 28 01:08:05 2018.
The blog has other interesting articles, e.g. https://stevelosh.com/blog/2018/08/a-road-to-common-lisp/, https://stevelosh.com/blog/2013/09/teach-dont-tell/

Information about keyboard handling and rebinding in Windows.

An improved keyboard layout (better than Dvorak), optimised for german. The page also has links to web design and maybe more.

Notes about keyboard bindings for the sawfish window manager.

Good tips to make OSX more convenient for people accustomed to Emacs.