Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
Number five from the same submitter, makes my job easy.
Source Dima Shiper
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A beautiful dark padded pattern, like an old classic sofa.
Source Chris Baldie
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
Remixed from a drawing in 'Incidents on a Journey through Nubia to Darfoor', F. Ensor, 1891.
Source Firkin
This one is amazing, truly original. Go use it!
Source Viahorizon
This is the remix of "Colorful Floral Pattern Background 3" uploaded by "GDJ". Thanks.
Source Yamachem
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
The following repeating website background is colored in a blue gray color and resembles a concrete wall or something similar to it.
Source V. Hartikainen