It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
Prismatic Abstract Geometric Background 4
Source GDJ
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
Prismatic Curved Diamond Pattern 2 No Background
Source GDJ
Derived from a drawing in 'The Murmur of the Shells', Samuel Cowen, 1879.
Source Firkin
I guess this is inspired by the city of Ravenna in Italy and its stone walls.
Source Sentel
A background tile of dark textile. Made this a long time ago and just now decided to publish it.
Source V. Hartikainen
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
Here's a dark background pattern that contains a steel grid pattern as a texture. Use it as a website background or for other purposes. It's free!
Source V. Hartikainen
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
Prismatic Geometric Pattern Variation 2 With Background
Source GDJ
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
This one needs to be used in small areas; you can see it repeat.
Source Luca
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
The tile this is based on was adapted from an image that was uploaded to Pixabay by frolicsomepl. It can be had in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
From a drawing in 'Codogno e il suo territorio nella cronaca e nella storia'', Gio and Giarella Cairo, 1897.
Source Firkin
Prismatic Geometric Pattern Background 2
Source GDJ
Light gray version of the Binding pattern that looks a bit like fabric.
Source Newbury
From an image on opengameart.org shared by rubberduck.
Source Firkin
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
Element of beach pattern with background.
Source Rones
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ