Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A heavy hitter at 400x400px, but lovely still.
Source Breezi
Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Zero CC tileable moss or lichen covered stone texture, edited from pixabay. CC0
Source Sojan Janso
Inspired by a drawing in 'Poems', James Smith, 1881.
Source Firkin
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
Remixed from a raster on Pixabay that was uploaded by ArtsyBee.
Source Firkin
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
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
This background texture resembles stone. It may be used as a background on web pages or on some of their html elements (header, borders, menu bar, etc.). Just modify it for your needs.
Source V. Hartikainen
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
Prismatic Polka Dots Mark II 3 No Background
Source GDJ