Compared to people around me I seem to know a lot about fashion history, textiles and clothing in general.

Hot tip, like literally a hot tip, if you're having trouble being miserable in the hot weather this summer, try wearing 100% cotton, loose fitting clothes that cover your skin. 100% Linen or a linen/rayon blend is even better but pricey. Wear a hat. Polyester, acrylic, spandex, microfiber, they're all plastics that not only insulate you but don't absorb your sweat. That "moisture wicking technology" athletic clothing is always going on about is total bullshit. Wear a linen shirt in the sun with a breeze and marvel at the magic of evaporative cooling. Covering your skin with a hat and sleeves not only helps prevent sunburn, but is also your own portable shade. You know how much cooler it is in the shade, right?

You might look at pictures of old timey people all dressed in big dresses and long sleeve shirts and waistcoats in the old west and think "wow they must have been so uncomfortable!" but I bet you they were more comfortable than you in your polyester. Just ask a reenactor!

I can read UPC, ISBN, and EAN bar codes. Tear the numbers off the bottom, hand me the lines, and I can tell you the numbers you tore off. Also, if you give me any specific date on the Gregorian calendar (on or after October 15, 1582), I can tell you the day of the week it was or will be on.

Finally...way less interesting...but I have a Master's degree in math and have taught elementary, middle school, high school, dual credit, and college math classes.

I can read and write using the Standard Galactic Alphabet from the Commander Keen series

I've always agreed with that saying "jack of all trades, master of none, but better than master of one" ... but I didn't expect to feel so frustrated that I don't have any fun niche knowledge.

This was a great question, and I've loved reading all the answers!

Acoustic propagation. I design large format PA systems and as a result need to know both how to make sound and stop sound at a large scale. It is entirely possible and actually relatively easy to be super precise with where sound goes or doesn’t go. The problem is cost.

I'm a professional fire/sideshow performer and certified freak. I know a lot about things that are weird, morbid, or dangerous. I also have a split tongue and love to show it off. I'm fun at parties :)

Ask me anything I guess?

For some reason I remember a lot of ANSI terminal escape codes. They were used all the time on DOS machines, and work in a similar way on Unix terminals.

Imagine a Venn Diagram with three circles:

Ships and their electronics
Linux servers
Industrial robotics

I'm in the middle where all of those intersect. Pays well.

A really painful type of coordinate transformation I once had to develop to try and shed some insight on Hawking radiation near black holes.

Unfortunately the results were fucking ugly and I gave up trying to understand them, largely due to the fact that except under very specific circumstances they're basically impossible to calculate (you get something similar to divide by zero errors).

Nice case:

Not nice case:

There was a ton more related stuff I could have spent a PhD working on, but life didn't really allow it (and frankly I'm okay with that, I'm actually doing enjoyable stuff for the first time in my life instead of fighting my brain).

If you need an expert on the long-discontinued Motorola 96002 digital signal processor, I'm your guy! I wrote an entire graphical operating system in its assembly language and still need to maintain it from time to time, so my skills remain sharp.

I'm able to identify a lot of music from the first beat / note. But only music that I know, which doesn't include a lot of mainstream pop.

I got way too hard into the Minecraft anarchy scene so I've got knowledge that even Minecraft fans find abhorrent.

Setting up bots and automation, using server exploits to hunt for hidden bases, exploiting item duplication glitches, and of course using cheat clients. I've even written a few hacks for a private client my group used to make.

I don't know how to articulate an answer to this right now, but I wanted to say that this was a great question, OP — there's some really cool answered here

I once worked for a company that designed "educational" programs that turned out to be little more than glorified corporate propaganda!

Ask me what the appropriate level of cynicism should be when it comes to anything related to "corporate culture."

Go on... ask me.

I have a lot of niche knowledge about specific issues relating to different brands/models of laptops and phones. it's very rare I find an issue I can't diagnose within an hour with prior knowledge. ask me anything I suppose?

oh, also, I happen to know that Ohio is the only state that doesn't share a letter in common with the word mackerel. works for the territories too. doesn't really get more niche than that.

I've been learning about air quality consultation as a backup business plan over the past few years. Buying commercial-grade sensors, researching various aspects of air quality, monitoring, and purification techniques. Nothing crazy but feels pretty niche to me.

I know how RuneScape's bot detection works, and currently have an OSRS account that's nearly maxed from nonstop botting over the last 6 months

Edit: I'm so confident (or maybe stupid) I'll even share my progress: https://secure.runescape.com/m=hiscore_oldschool/hiscorepersonal?user1=nk%20best%20k

I am a steadicam operator and have been making power cables for cameras. I get calls from around the USA and the world from people trying to troubleshoot their electrical systems on their Steadicam and cinema cameras.

I can look at a blueprint (top, front, and side views) and imagine the object in 3D. This is probably why I find topo maps easy to read as well.

I've delved way too deep into the fall of the Western Roman Empire. I think I know a lot about Majorian, Stilicho, Aetius and Ricimer. My gf at this point even knows who Honorius is and why he was a bad emperor. Edit: and that he had chicken :)

When I saw the meme "How often do you daily think about the Roman Empire", I knew that it was about me, because the answer is yes :/

I am an expert on disaster response preplanning for hospitals and have basically read every English, German and Italian publication on that matter. Sadly that does not pay well...

• I am a beast at movie and tv themes
• I'm very good at guessing boardgames from just very few clues (bu i think that part of that skill is that people who ask usually don't ask for the deep knowledge)
• I have a triggerable wealth of knowledge about random trivia facts. During some conversations i will just randomly remember something related to the current topic and then spout it. My goto fact when someone asks me to give some random trivia is that alpaccas have a set of razor sharp teeth between their molars that they use mainly to bite off other alpaccas testicles

Reading books on natural philosophy. By that I mean, not mathematics of the physics itself, but what do the mathematics actually tell us about the natural world, how to interpret it and think about it, on a more philosophical level. Not a topic I really talk to many people irl on because most people don't even know what the philosophical problems around this topic. I mean, I'd need a whole whiteboard just to walk someone through Bell's theorem to even give them an explanation to why it is interesting in the first place. There is too much of a barrier of entry for casual conversation.

You would think since natural philosophy involves physics that it would not be niche because there are a lot of physicists, but most don't care about the topic either. If you can plug in the numbers and get the right predictions, then surely that's sufficient, right? Who cares about what the mathematics actually means? It's a fair mindset to have, perfectly understandable and valid, but not part of my niche interests, so I just read tons and tons and tons of books and papers regarding a topic which hardly anyone cares. It is very interesting to read like the Einstein-Bohr debates, or Schrodinger for example trying to salvage continuity viewing a loss of continuity as a breakdown in classical notion of causality, or some of the contemporary discussions on the subject such as Carlo Rovelli's relational quantum mechanics or Francois-Igor Pris' contextual realist interpretation. Things like that.

It doesn't even seem to be that popular of a topic among philosophers, because most don't want to take the time to learn the math behind something like Bell's theorem (it's honestly not that hard, just a bit of linear algebra). So as a topic it's pretty niche but I have a weird autistic obsession over it for some reason. Reading books and papers on these debates contributes nothing at all practically beneficial to my life and there isn't a single person I know outside of online contacts who even knows wtf I'm talking about but I still find it fascinating for some reason.

I’m an expert in consequential greenhouse gas accounting. Which is the sub discipline of GHG accounting that specializes in understanding how policies and decisions impact global GHG emissions.

I stumbled into an optics development project over a decade ago. Today I develop multiple systems a year and know the math behind it pretty well, although I use the dedicated software. I've also worked on the manufacturing of lenses. I've always been into photography and hope to start a niche camera lens company in the US just like MS optics in Japan.