Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Sounds like something from World of Warcraft. Has to be good.
Source Tony Kinard
Prismatic Abstract Geometric Background 5
Source GDJ
Hexagonal dark 3D pattern. What more can you ask for?
Source Norbert Levajsics
A pattern derived from part of a fractal rendering in Paint.net.
Source Firkin
Fix side and a seamless pattern formed from circles.
Source SliverKnight
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
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
More carbon fiber for your collections. This time in white or semi-dark gray.
Source Badhon Ebrahim
Produced using the clouds, flames and glass blocks plug-ins in Paint.net and the resulting .PNG vectorised with Vector Magic.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin