Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
The image depicts a seamless pattern of pine tree leaves.
Source Yamachem
Greyscale version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
White circles connecting on a light gray background.
Source Mark Collins
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Colour version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
A bit like smudged paint or some sort of steel, here is scribble light.
Source Tegan Male
A seamless stone-like background for blogs or any other type of websites.
Source V. Hartikainen
This was formed by distorting an image of a background on Pixabay.
Source Firkin
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
From a drawing in 'Cassell's Library of English Literature', Henry Morley, 1883.
Source Firkin
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
Here's a repeatable texture that resembles a light green concrete wall or something similar.
Source V. Hartikainen
Light gray version of the Binding pattern that looks a bit like fabric.
Source Newbury
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
You know you love wood patterns, so here’s one more.
Source Richard Tabor
Lovely light gray floral motif with some subtle shades.
Source GraphicsWall
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski