A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Background formed from the original with an emboss effect.
Source Firkin
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
Light gray paper pattern with small traces of fiber and some dust.
Source Atle Mo
Prismatic Abstract Geometric Background 4
Source GDJ
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
Kaleidoscope Prismatic Abstract No Background
Source GDJ
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Pattern formed from simple shapes. Black version.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski
Derived from a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Light and tiny, just the way you like it.
Source Rohit Arun Rao
Prismatic Polyskelion Pattern No Background
Source GDJ
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Same classic 45-degree pattern, dark version.
Source Luke McDonald
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin