This one has rusty dark brown texture.
Source V. Hartikainen
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
Greyscale version of a pattern that came out of playing with the 'slinky' plug-in for Paint.net
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 of dark bricks. Maybe it's not very realistic, but it looks good in my opinion.
Source V. Hartikainen
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
Inspired by a drawing in 'Poems', James Smith, 1881.
Source Firkin
A very dark spotted twinkle pattern for your twinkle needs.
Source Badhon Ebrahim
Seamless tile drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Sharp diamond pattern. A small 24x18px tile.
Source Tom Neal
From a design in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin
Sharp pixel pattern, just like the good old days.
Source Paridhi
Prepared mostly as a raster in Paint.net and vectorised.
Source Firkin
A free repetitive background with a dark concrete wall like texture. This one may be used in dark web site designs.
Source V. Hartikainen
Another fairly simple design drawn in Paint.net and vectorized in Inkscape.
Source Firkin
Light gray paper pattern with small traces of fiber and some dust.
Source Atle Mo
Seamless Dark Grunge Texture. Here's a new grunge texture for use as a background.
Source V. Hartikainen
Prismatic Curved Diamond Pattern 3 No Background
Source GDJ
Prismatic Abstract Geometric Background 3
Source GDJ