LOW←TECH MAGAZINE Magazine about "past and forgotten technologies"
 Runs from a solar panel, so will sometimes be offline.

Solar ePaper Photo Frame (jamez.it)

DRCOS Free Sewing Patterns

STEPPER (Bad Diode) - 16 Step Sequencer for GBA

CO₂ Monitor (Larry Bank) - CO₂ Monitor using SCD41
 The SCD41 looks very interesting, it detects CO₂ directly and not inferring it.

Adafruit GFX Font Customiser (tchapi)

Embroidered Computer (Irene Posch)

How to Use Static Site Generator Pelican (Charles Reid)
 Which, uh, I should probably get to using to actually get this site running...

Unconventional Computer Thread Copy of a fediverse thread listing & discussing
 unconventional computers and associated ideas.

Firefox Sidebar Tabs Configuration
 Using Sidebery Addon. (You can unload tabs with it!)

Marginalia Search Experimental Small Search Engine

File over App (Steph Ango)

Making Watercolour Paint from Slate (estfyr)
 Also from Brick

Simplifier Creating Early Tech Hardware

The Website Obesity Crisis (Maciej Cegłowski)

Deconstruction Mindset (Kira)

Plant Database

Fire-based Triode (Nyle Steiner)

Emoji History: The Missing Years (gingerbeardman) Pre-1997 Emoji

My4TH (Dennis Kuschel) Discrete Logic CPU Forth Computer
  Forth Deck My4TH in a portable computer

Lospec Catalogue of palettes, also has pixel art

XFCE Themes - How To

Cyberdeck Cafe - Building guide

Carpentopod (Giliam de Carpentier) Think Strandbeest, but table.

List of Algorithms (Wikipedia)

Public.work Search engine for public domain images.

The Linkfest Fortnightly list of interesting links. (Clive Thompson)

Make It Yourself Digital book linking to 1000 DIY projects. (N-O-D-E)
  [Topics include computing, hiking, fashion, gardening, and others. There's stuff here for multiple diciplines, and each project has icons indicating which ones are reqired between 3D printing, sewing, woodworking, laser cutting, electronics, leatherworking, CNC milling, papercraft, and metalworking.]
  Also N-O-D-E's website, and youtube account. (Though youtube is rarely updated)

Weird Old Book Finder (Clive Thompson) Search engine for weird old books.

Search Engines with their own Indexes (Seirdy)

Personal Sites/Blogs/Wikis

XXIIVV (Devine Lu Linvega, part of Hundred Rabbits)

Kokorobot (Rek Bell, part of Hundred Rabbits)
 Spellbook for Terminal stuff.

Josh On Design Blog About Programming
 Typographic Programming Language

Maggie Appleton Essays About Programming

Video Game Stuff

Romhacking Romhacks, Translations, and romhacking Tools

Hit Save - e-Reader Card Preservation Video Game Preservation

Gaming Alexandria Game Preservationist Blog

SMS Power - Sega AI Computer Preservation of the Sega AI Computer.
 A Prolog based microcomputer from 1986. They have a MAME emulator.

Gameboy Camera Mini Custom Gameboy Camera Cart

RomHacking.net Romhacks and Translations, mostly for older games.

Knitting Machine

MKManuals Knitting Machine manuals, magazines etc.
 In the format of a shop, but it's all free. ¯\_(ツ)_/¯

Brother Knitting Machines Accessory Compatibility

List of Punchcard Sets (in pdf)

mostlyknittingmachines User and Service Manuals

Lists

"Delightful Creative Tools" (ADHDefy) - List of 2D, 3D, Audio, Writing, Coding. I believe all are FOSS.

Pictures (corkami) - File Format Cheatsheets and other stuff

Maker Skill Tree (sjpiper145) - 'Skill tree' of small goals and milestones for many skills and hobbies

Art Resource Database [Google Docs] (Scazrelet) - Huge list of resources,
 from software, references, tutorials, blogs, etc.

Awesome Bluesky Tools and stuff related to Bluesky

Weird Desktop Environments

Starcel (Nick Maleki) [2GB, Windows only] 3D DE, scaling, plotting, etc. It looks wild.
 Haven't tried it yet, though.

GodotOS (popcar2) [~22MB, Linux, Windows] Toy DE made in Godot, pretty standard, but cute.

hackaday.io

PotatoP (Andreas Eriksen) - Low Power, Memory Display, LISP machine

Tern (Mechanical Advantage) - Ternary Logic

Low Power ESP32 Handheld (Max.K) - Memory Display, Gyro-based cursor

PICOmputer (bobricius) - RP2040 Handheld Computer

ARMACHAT (bobricius) - Handheld LoRa Messenger

Light Logic (Dr. Cockroach) - Transistorless Logic, LEDs and CdS photo resistors

Lossy Text Compression (Greg Kennedy)

Internet Archive

How to Build a Working Digital Computer [1968]
 by Edward Alcosser, James P Phillips, Allen M. Wolk

Papers

Mirages: On Anthropomorphism in Dialogue Systems
 by Gavin Abercrombie, Amanda Cercas Curry, Tanvi Dinkar, Zeerak Talat
 Deanthropomorphising LLM chatbots

The Design of a Relay-Based Computer (PDF, 92 pages, 11.4MB)
 by Harry Porter
 Hosting here because the site it was on died like the day after I found it. Had to snatch it from Wayback Machine.

The Cuneiform Tablets of 2015
 by Long Tien Nguyen, Alan Kay
 Software preservation

Webrings

XXIIVV

Homebrew CPU Ring

Typefaces/Fonts

Uncut.wtf Open Source Fonts

Freefaces.gallery Curated collection, variety of free licences.

Creating a Typeface from your Handwriting with FontForge (Rek Bell)
 [I know there used to a be a site that would do this automatically, but I believe it shut down a while ago]