Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Imagine you zoomed in 1000X on some fabric. But then it turned out to be a skeleton!
Source Angelica
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
A browner version of the original weathered fence texture.
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
The image depicts a seamless pattern of a fishnet with a plenty of fish.It may be a lucky charm for fishermen.
Source Yamachem
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Groovy Concentric Background 4
Source GDJ
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
A tile-able background for websites with paper-like texture and a grid pattern layered on top of it.
Source V. Hartikainen
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
Prismatic Chevrons Pattern 5 With Background
Source GDJ
A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
A seamless pattern the starting point for which was a 'light rays' rendering in Paint.net.
Source Firkin
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
Alternative colour scheme. 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
Prismatic Polka Dots Mark II 3 No Background
Source GDJ
From a drawing in 'Uit de geschiedenis der Heilige Stede te Amsterdam', Yohannes Sterck, 1898.
Source Firkin
Lovely pattern with some good-looking non-random noise lines.
Source Zucx
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
One more sharp little tile for you. Subtle circles this time.
Source Blunia
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A very dark spotted twinkle pattern for your twinkle needs.
Source Badhon Ebrahim
A seamlessly tile-able grunge background image.
Source V. Hartikainen
Prismatic Abstract Line Art Pattern Background 2
Source GDJ