If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
Remixed from an image on Pixabay uploaded by Prawny
Source Firkin
No, not the band but the pattern. Simple squares in gray tones, of course.
Source Atle Mo
A comeback for you: the popular Escheresque, now in black.
Source Patten
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Almost like little fish shells, or dragon skin.
Source Graphiste
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
I have no idea what J Boo means by this name, but hey – it’s hot.
Source j Boo
A free repetitive background with a dark concrete wall like texture. This one may be used in dark web site designs.
Source V. Hartikainen
I love these crisp, tiny, super subtle patterns.
Source Badhon Ebrahim
Remixed from a drawing in 'Prehistoric Man: researches into the origin of civilisation in the old and the new world', Daniel Wilson, 1876.
Source Firkin
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
Your eyes can trip a bit from looking at this – use it wisely.
Source Michal Chovanec
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
Colour version of the original pattern inspired by the front cover of 'Old and New Paris', Henry Edwards, 1894.
Source Firkin
By popular request, an outline version of the pentagon pattern.
Source Atle Mo
Here's a seamless brown cork board background texture. Feel free to download or reshare if you like.
Source V. Hartikainen