Did some testing with Repper Pro tonight, and this gray mid-tone pattern came out.
Source Atle Mo
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
A seamless textured paper for backgrounds. Colored in pale orange hues.
Source V. Hartikainen
A background pattern with green vertical stripes. A new striped background pattern. This time a green one.
Source V. Hartikainen
Zero CC tileable cork floor, photographed and made by me. CC0
Source Sojan Janso
A free tileable background colored in off-white (antique white) color.
Source V. Hartikainen
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Lovely light gray floral motif with some subtle shades.
Source GraphicsWall
A bit of scratched up grayness. Always good.
Source Dmitry
Fake or not, it’s quite luxurious.
Source Factorio.us Collective
This background pattern looks like bamboo to me. Feel free to download it for your website (for your blog perhaps?).
Source V. Hartikainen
Remixed from a drawing that was uploaded to Pixabay by captenpub.
Source Firkin
Seamless Olive Green Web Background Image
Source V. Hartikainen
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
An abstract Background pattern of purple twisty patterns.
Source TikiGiki
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous
Just like your old suit, all striped and smooth.
Source Alex Berkowitz
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin