The open source community has a big, big problem with clearly documenting its work. Technical writing should not be considered optional. If you create something, explain how to use it from the beginning, with context, overviews, and little assumed prior knowledge. Incomprehensibility isn't a sign of brilliance, it's a sign of the opposite. Consider Feynman!

Now, without context and explanation I present a bunch of random notes:

Debian (Linux) notes

Raspberry Pi notes

ROS notes

Personal website:

An important magazine: