Clickspring is currently recreating the antikythera mechanism using period accurate tools and technology, which is low tech if you consider that it was high tech for the ancient greeks.
Not directly answering your question, but if you haven't already you should take a look at the end of life disaster recovery repo.
Yes, it really is that bad. We have a resin printer at work and it has been banished to a different room due to the resin fumes. The table it sits on is perpetually sticky, and we go through twice as much IPA postprocessing the prints than we use in resin
Cataclysm: Dark Days Ahead. Zombie survival roguelike, forked from the original cataclysm by whales. Also check out Cataclysm: Bright Nights which is a fork of CDDA that makes it more gamey like the original, and less like you're playing 2d arma.
Sunshine and moonlight are open source implementations of nvidia's game streaming protocol they created for the nvidia shield. You can use it to remotely use your computer from your phone, not just for games. But of course the primary application is game streaming. As long as the game can run on the host (sunshine) computer, you can remotely play it on the client (moonlight) device. I've used it to just launch steam in big picture mode and then select what I want from steam.
Obtainium lets you install FOSS programs directly from the developers source. You can get updates from the github/gitlab of app developers before they get uploaded to F-droid.
Hyperrogue is not quite a top down hexagon world, it's a top down heptagon world. The premise is that it is a roguelike set in a hyperbolic world, and different regions teach you different weird properties of a hyperbolic space. For example, the crossroads feature an infinite amount of parallel lines and yet there are still forks in the pathway.
Even though it's foss, it is also for sale on steam if you want to support the dev
Nobody tell banks about fortnights
Near the bolt holes joining the two halves, you can see thin strips going across that overhang gap. Those eliminate local sagging without needing support material. The part could have been flipped 180 instead, but then the outer edge rim would be unsupported.
The monoblock was a prototype watercooling block that interfaced with the cpu and gpu simultaneously. Normally if you wanted to watercool both components one would purchase seperate waterblocks for the cpu and gpu and then use plumbing in between the two.
Going to submit my probably-not-a-puzzle-game-game: rhythm games. The game tells you exactly what to press and when you're supposed to press it, it's just up to you to actually press the buttons. See: DDR, Rhythm Doctor.
Note that there are rhythm games that have more decision making like crypt of the necrodancer (rhythm roguelike)