A nice one indeed, but I have a feeling we have it already? If you spot a copy, let me know on Twitter.
Source Graphiste
Prismatic Polka Dots Mark II No Background
Source GDJ
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
Dark blue concrete wall with some small dust spots.
Source Atle Mo
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.
Source Paul Phönixweiß
This light yellow background pattern consists of an irregular pattern of spots. Here's a light background pattern with yellowish tint.
Source V. Hartikainen
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Zero CC tileable hard cover cells, skin like, book texture. 4K, Scanned and made by me CC0
Source Sojan Janso
Nothing like a clean set of bed sheets, huh?
Source Badhon Ebrahim
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
Otis Ray Redding was an American soul singer-songwriter, record producer, arranger, and talent scout. So you know.
Source Thomas Myrman
The starting point for this was drawn on the web site steamcoded.org/PolyskelionMaker.svg
Source Firkin
An abstract Background pattern of purple twisty patterns.
Source TikiGiki
A seamless green background texture. The image is distributed under a Creative Commons License (like all of the images here).
Source V. Hartikainen
Thin lines, noise and texture creates this crisp dark denim pattern.
Source Marco Slooten
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski