Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Geometric lines are always hot, and this pattern is no exception.
Source Listvetra
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
The basic shapes never get old. Simple triangle pattern.
Source Atle Mo
I’m starting to think I have a concrete wall fetish.
Source Atle Mo
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
This one looks like a cork panel. Feel free to use it as a tiled background on your blog or website.
Source V. Hartikainen
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
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
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
Original minus the background
Source Firkin
You were craving more leather, so I whipped this up by scanning a leather jacket.
Source Atle Mo
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin