Linux

There was this distro that stuffs everything of a package in one folder, instead of /usr/lib & co. What was it called again?

Maybe not some obscure ones, but here are some lesser known ones:

Talos Linux. It's an immutable operating system designed specifically to deploy kubernetes.

OpenSuse Harvester Think Proxmox, but instead of VM's and LXC containers, it's VM's and Kubernetes.

XCP-NG is a RHEL based distro designed for managing Linux virtual machines using the xen hypervisor, as opposed to KVM. Think Proxmox, but RHEL and Xen (also no LXC). However, it does not come with a web ui out of the box, you have to deploy it yourself. Technically, XCP is a Xen distribution, since Xen is a kernel with nothing but a hypervisor that runs under the main distro, but the primary management virtual machine is RHEL based, and uses Linux.

Speaking of Proxmox, Proxmox is technically a Linux distro.

SnowflakeOS is a project that aims to bring a GUI focused experience to NixOS.

TurnkeyLinux (site is loading very, very slowly for me right now) is not a single distribution, but rather a set of debian based distributions that are designed to be turnkey appliance virtual machines that contain and host a specific app. To deploy the app, all you have to do is set up the virtual machine.

Now, here are some not-linux, but interesting distros:

SmartOS. They ported KVM to unix, and also can use Linux syscall translation (similar to wine) to run apps in containers as well. There is also Bhyve. It's a very interesting hypervisor platform.

OmniOS is similar. Bhyve, KVM, and Linux syscall translation in containers.

Rarely hear about DSL anymore, http://www.damnsmalllinux.org/

If being usable is a metric, Slackware

I see no one has mentioned Bedrock Linux yet. Not sure though how others would rate its 'obscurity' though. It's definitely a standout among distros.

Suicide linux. Nobody can run it for more than a day

Edit: i just searched "suicide linux" to see if it still exists and one of the top results was ian murdock's wiki page, :(

most obscure and to me coolest but unfortunately not very active https://sourcemage.org/

I'm gonna go with Tom's Root Boot. Or maybe the father of all live distros, Knoppix.

Yellow Dog

I actually ran this on a PPC Mac back in the day

Take your pick from the Linux family tree

No one mentioned Bunsenlabs or Crunchbang Linux here, but they aren't really that obscure.

2 days ago my friend found an old SATA hard drive and gave it to me to check what's on it, and me, not having a disk station or anything, and against all better judgment, I just swapped the disk in my laptop for my friend's, and instead of my laptop being fried it turned out the disk was running something called Crunchbang Linux

https://www.qubes-os.org/statistics/

Well I don’t hear much about Gentoo, Damn Small, Puppy or Knoppix anymore. Wonder if they still exist.

I haven’t done much disto hopping since I settled on Ubuntu around ‘08 and then on NixOS last year. I like my systems working when I need them and waiting around for a new install to finish is boring to me.

United Linux - the famous Red Hat Enterprise Linux killer!

https://en.wikipedia.org/wiki/United_Linux

The old PearOS(which looked like a meme-ish knockoff MacOS), UwUntu and Nyarch

I imagine there was a time when this wasn't obscure, but I'm guessing people today don't remember Caldera OpenLinux. That was the first Linux distro I installed/used. A guy from church gave his copy.

Caldera eventually became SCO. But I'm pretty sure I was using Caldera OpenLinux before the whole Novell patent suit thing.

SLiTaz

It's an obscure originally live usage oriented distro that you could also install. It was the first *Nix I ever used.

Obscure as in "only for a very specific purpose and nothing else"?...

Well, there is the Mircrosoft linux distro for their azure cloud

I guess DD-WRT as distro for router is also kind of obscure. Or the more general openWRT for embedded systems.