Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Black & white version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin
It looks very nice I think.
Source V. Hartikainen
Dark wooden pattern, given the subtle treatment. based on texture from Cloaks.
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
Background formed from the original with an emboss effect
Source GDJ
Semi-light fabric pattern made out of random pixels in shades of gray.
Source Atle Mo
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
From a drawing in 'Cassell's Library of English Literature', Henry Morley, 1883.
Source Firkin
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra
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
A white version of the very popular linen pattern.
Source Ant Ekşiler
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Prismatic Curved Diamond Pattern 7 No Background
Source GDJ
Alternative colour scheme for the original floral pattern.
Source Firkin
Abstract Ellipses Background Grayscale
Source GDJ
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
Abstract Tiled Background Extended 8
Source GDJ
Derived from an image that was uploaded to Pixabay by mdmelo.
Source Firkin
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev