People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
Feel free to download this "Dark Wood" background texture for your web site. The background tiles seamlessly!
Source V. Hartikainen
A white version of the very popular linen pattern.
Source Ant Ekşiler
Original seamless pattern with an Inkscape filter.
Source Firkin
Seamless Prismatic Geometric Pattern With Background
Source GDJ
From a drawing in 'Codogno e il suo territorio nella cronaca e nella storia'', Gio and Giarella Cairo, 1897.
Source Firkin
A pale orange background pattern with glossy groove stripes.
Source V. Hartikainen
Orange-red pattern for tiled backgrounds.
Source V. Hartikainen
Prismatic Abstract Background Design
Source GDJ
Otis Ray Redding was an American soul singer-songwriter, record producer, arranger, and talent scout. So you know.
Source Thomas Myrman
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Remixed from a PNG that was uploaded to Pixabay by k_jprather
Source Firkin
Here's an yet another seamless note paper texture for use as a background on websites.
Source V. Hartikainen
There are many carbon patterns, but this one is tiny.
Source Designova
A light gray wall or floor (you decide) of concrete.
Source Atle Mo
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Some rectangles, a bit of dust and grunge, plus a hint of concrete.
Source Atle Mo
Prismatic Abstract Line Art Pattern Background 2
Source GDJ