A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Remixed from a JPG that was uploaded to Pixabay by theasad121
Source Firkin
Like the name suggests, this background image consists of a pattern of dark bricks. It may be an option for you, if you are looking for something that looks like a brick wall for use as a background on web pages. It's not a masterpiece, but looks pretty nice when is tiled.
Source V. Hartikainen
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
A very dark asfalt pattern based off of a photo taken with my iPhone.
Source Atle Mo
Not the Rebel alliance, but a dark textured pattern.
Source Hendrik Lammers
Lovely light gray floral motif with some subtle shades.
Source GraphicsWall
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
A free seamless background pattern for use on websites.
Source V. Hartikainen
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
It’s like Shine Dotted’s sister, only rotated 45 degrees.
Source mediumidee
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
Prismatic Geometric Pattern Background 2
Source GDJ
Thin lines, noise and texture creates this crisp dark denim pattern.
Source Marco Slooten
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
Abstract Tiled Background Extended 12
Source GDJ
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Light gray version of the Binding pattern that looks a bit like fabric.
Source Newbury
Square design drawn in Paint.net and vectorized in Vector Magic.
Source Firkin