People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
Used a cherry by doctormo to make this seamless pattern
Source Firkin
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Pattern produced in Paint.net using the Vibrato plug-in.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
All good things come in threes, so I give you the third in my little concrete wall series.
Source Atle Mo
Classic 45-degree pattern, light version.
Source Luke McDonald
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Light gray paper pattern with small traces of fiber and some dust.
Source Atle Mo
Inspired by a drawing in 'Poems', James Smith, 1881.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Remixed from a drawing in 'Line and form", Walter Crane, 1914.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Colorful Floral Background 3 No Black
Source GDJ