A bit like smudged paint or some sort of steel, here is scribble light.
Source Tegan Male
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
A pattern formed from a photograph of a 16th century ceramic tile.
Source Firkin
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
Have you wondered about how it feels to be buried alive? Here is the pattern for it.
Source Hendrik Lammers
The original enhanced with some gradients.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.
Source Paul Phönixweiß
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Farmer could be some sort of fabric pattern, with a hint of green.
Source Fabian Schultz
Background formed from the original with an emboss effect
Source GDJ
No idea what Nistri means, but it’s a crisp little pattern nonetheless.
Source Markus Reiter
Seamless pattern inspired by a drawing on Pixabay. To get the tile this is formed from, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
Number 3 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
Might not be super subtle, but quite original in its form.
Source Alex Smith
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
A pattern derived from repeating unit cells each derived from part of a mosaic in paint.net. The starting point for the mosaic was a picture of some prawns!
Source Firkin