CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Light gray pattern with an almost wall tile-like appearance.
Source Markus Tinner
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Redrawn based on a drawing in 'По Сѣверо-Западу Россіи' Konstantin Sluchevsky, 1897.
Source Firkin
I’m guessing this is related to the Sony Vaio? It’s a nice pattern no matter where it’s from.
Source Zigzain
A dark background pattern/texture of a dimpled metal plate.
Source V. Hartikainen
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Prismatic Abstract Background Design No Black
Source GDJ
Seamless pattern the basic tile for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Derived from a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
A dark pattern made out of 3×3 circles and a 1px shadow. This works well as a carbon texture or background.
Source Atle Mo
Number 2 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
This background image is great for using in web design or graphic design projects. And don't forget to visit the homepage. I frequently update this resource with fresh tileable backgrounds.
Source V. Hartikainen
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
This is a seamless pattern of regular hexagon which has a honeycomb structure.
Source Yamachem
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
This one needs to be used in small areas; you can see it repeat.
Source Luca
Prismatic Groovy Concentric Background 3
Source GDJ
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Tile-able Dark Brown Wood Background. Feel free to use it as a background image in your designs or somewhere on the web. By the way, the color seems to be close to Coffee Brown.
Source V. Hartikainen