To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Thin lines, noise and texture creates this crisp dark denim pattern.
Source Marco Slooten
Looks like an old wall. I guess that’s it then?
Source Viahorizon
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A version without colours blended together to give a different look.
Source Firkin
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
The image depicts a seamless pattern of a Japanese family crest called "chidori" in Japanese .A chidori in Japanese means a plover in English.
Source Yamachem
Prismatic Abstract Background Design No Black
Source GDJ
Colorful Floral Background 3 No Black
Source GDJ
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
A beautiful dark padded pattern, like an old classic sofa.
Source Chris Baldie
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
You know you can’t get enough of these linen-fabric-y patterns.
Source James Basoo
Stefan is hard at work, this time with a funky pattern of squares.
Source Stefan Aleksić
A dark background pattern/texture of a dimpled metal plate.
Source V. Hartikainen
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
This is a seamless pattern which is derived from a flower petal image.
Source Yamachem
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin