Did some testing with Repper Pro tonight, and this gray mid-tone pattern came out.
Source Atle Mo
Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Derived from a drawing in 'The Murmur of the Shells', Samuel Cowen, 1879.
Source Firkin
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
You know I love paper patterns. Here is one from Stephen. Say thank you!
Source Stephen Gilbert
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Embossed lines and squares with subtle highlights.
Source Alex Parker
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Prismatic Groovy Concentric Background 5
Source GDJ
Prismatic Groovy Concentric Background 3 No Black
Source GDJ
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
The tile for this is based on a repeating unit close to a design on Pixabay. It can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
Can’t believe we don’t have this in the collection already! Slick woven pattern with crisp details.
Source Max Rudberg
Farmer could be some sort of fabric pattern, with a hint of green.
Source Fabian Schultz
Feel free to use this seamless background texture as a background on a web site. It's colored in a light pink color and is seamlessly tile-able.
Source V. Hartikainen
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'From Snowdon to the Sea. Striking stories of North and South Wales', Marie Trevelyan, 1895.
Source Firkin