Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
I scanned a paper coffee cup. You know, in case you need it.
Source Atle Mo
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I. Version with black background.
Source Firkin
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Feel free to download this "Dark Wood" background texture for your web site. The background tiles seamlessly!
Source V. Hartikainen
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
If you don’t like cream and pixels, you’re in the wrong place.
Source Mizanur Rahman
Black & white version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
Prismatic Triangular Seamless Pattern III With Background
Source GDJ
On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.
Source Paul Phönixweiß
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
This is a seamless pattern which is derived from a flower petal image.
Source Yamachem
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Oh yes, it happened! A pattern in full color.
Source Atle Mo
From a drawing in 'Heroes of North African Discovery', Nancy Meugens, 1894.
Source Firkin