Some rectangles, a bit of dust and grunge, plus a hint of concrete.
Source Atle Mo
Nice and simple crossed lines in dark gray tones.
Source Stefan Aleksić
Inspired by a JPG that was uploaded to Pixabay by kokon_art
Source Firkin
A grayscale fabric pattern with vertical lines of stitch holes.
Source V. Hartikainen
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
A background pattern with wavy green vertical stripes. This one has green stripes on a white background. Download if you like it.
Source V. Hartikainen
Greyscale version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
Zero CC bark from fur tree tileable texture, photographed and made by me. CC0
Source Sojan Janso
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
Found on the ground in french cafe in kunming, Yunnan, china
Source Rejon
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i
Source Firkin
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin
I love cream! 50x50px and lovely in all the good ways.
Source Thomas Myrman
Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous