Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
A seamless marble-like texture colored in light blue.
Source V. Hartikainen
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I. Version with black background.
Source Firkin
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
Prismatic Groovy Concentric Background 4
Source GDJ
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
This seamless web background texture looks like gray stone. It's great for using as a background image on web pages, or on some of their elements. Anyway, I hope you will find use for it.
Source V. Hartikainen
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
Prismatic Groovy Concentric Background No Black
Source GDJ
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
From a drawing in 'Artists and Arabs', Henry Blackburn, 1868
Source Firkin
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
This one needs to be used in small areas; you can see it repeat.
Source Luca
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
Source Firkin
Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
A comeback for you: the popular Escheresque, now in black.
Source Patten