The following repeating website background is colored in a blue gray color and resembles a concrete wall or something similar to it.
Source V. Hartikainen
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
A seamless pattern based on a tile that can be achieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A blue gray fabric-like texture for websites. An yet another fabric-like texture. It has subtle vertical and diagonal stripes to it.
Source V. Hartikainen
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim
This background pattern contains a seamless texture of bark. It's not very realistic, but I think it looks quite nice.
Source V. Hartikainen
Derived from a PNG that was uploaded to Pixabay by nutkitten
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
A comeback for you: the popular Escheresque, now in black.
Source Patten
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
Bright Multicolored Floral Background by Karen Arnold from PDP.
Source GDJ
From a drawing in 'Cassell's Library of English Literature', Henry Morley, 1883.
Source Firkin
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
Semi-light fabric pattern made out of random pixels in shades of gray.
Source Atle Mo