/soy/ - Soyjaks

This is a genuinely difficult exercise because the list mixes fictional events, logical paradoxes, absurdly narrow trivia, real niche topics, and things that affect billions of people. I've ordered them by a combination of: does it even exist?, how many people have a reason to care?, and does it have practical consequences?

TIER 3: "Real, with a small but genuine community"

(Hundreds to low thousands of people care)

Methods for waterproofing manuscripts in tropical climates — Real archival concern, especially in Southeast Asian libraries.
Playing the hydraulophone — A real instrument. The community of players is small but enthusiastic.
The chemical reactions that happen during 3D printing — Real and varies by process (photopolymerization in SLA, sintering in SLS). Growing relevance.
Competitive cup stacking — A real sport with organized competitions and a small following.
The study of different types of fencing (chain-link, wrought iron, split-rail) — Real, mundane, but there are industry professionals who care.
Types of wood used in toothpicks — Surprisingly real industry knowledge (mostly birch, sometimes bamboo).
Minecraft 1.3.2 servers — Retro Minecraft community. Small but dedicated.
Downloading captions of YouTube videos from NewPipe — Practical question for a specific open-source app's user base.
Toki Pona syntax — A real constructed language with a small but passionate community (~thousands of speakers).
Traditional Turkic beliefs — Tengrism and related traditions. Real topic in anthropology and religious studies.
Structure of Masonic lodges — Well-documented, of interest to historians, Freemasons, and conspiracy theorists.
Assembly of a scanning electron microscope — Real scientific instrumentation. Relevant to lab technicians and materials scientists.

TIER 4: "Real, with established academic or professional relevance"

(Tens of thousands to millions of people have a reason to care)

The list of make-up artists that worked on the original Star Wars trilogy — Stuart Freeborn, Rick Baker, etc. Star Wars fandom is massive.
Economy of Vanuatu — A real country with a real economy. Relevant to development economists and Pacific Island studies.
The IPv5 protocol — Real networking history (ST-II, an experimental streaming protocol never widely deployed). Interesting to network engineers.
Julius Evola's esoteric fascist literature — Real, controversial, and actively studied in political science and extremism research.
The Arzelà–Ascoli theorem — A real and important result in functional analysis. Every math graduate student encounters it.
The standardization of paper sizes — ISO 216 (A4, etc.). Surprisingly fascinating to a broad audience once you start explaining the √2 ratio.
The Dvorak keyboard — Well-known alternative layout. Debated endlessly in tech circles.
Unix filenames — Fundamental computing concept. Every programmer deals with this.
The toxicity of varying parts of food vegetables — Genuinely practical. Rhubarb leaves, green potatoes, cherry pits — this affects everyone who cooks.

TIER 5: "Real, with broad practical or geopolitical importance"

(Millions to billions of people are affected)

The Iranian diaspora — A major geopolitical, sociological, and humanitarian topic affecting millions of people across the Middle East, Europe, and North America.
FIDO2 & WebAuthn implementations — The technology behind passkeys. Currently being rolled out to billions of users by Apple, Google, and Microsoft. Directly affects your online security.
The contents of the ISO C++ standard document — C++ underpins operating systems, game engines, browsers, and financial systems. Millions of developers depend on this.
The development of the Linux kernel versions 6 and 7, and open-source Windows NT kernel operating systems — Linux runs the internet, Android, supercomputers, and cloud infrastructure. This affects virtually everyone on Earth indirectly.
The eccentric orbit of Mercury around the Sun — The anomalous precession of Mercury's perihelion was one of the first confirmations of Einstein's general relativity. It's one of the most famous results in the history of physics.
The 55 officially recognized ethnic minorities in the People's Republic of China — A fundamental demographic and geopolitical fact about the world's most populous country, directly affecting over 100 million people and shaping global policy on human rights, autonomy, and cultural preservation.

TL;DR: At the bottom, you have things that are physically impossible, logically paradoxical, or outright fictional. At the top, you have things that shape the lives of billions of people and the infrastructure of modern civilization. The Windows 98 startup sound corruption question remains the king of shit nobody cares about because it's not even wrong — it's meaningless.