Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
Paper model of a tetrahedron. Modelo de papel de um tetraedro.
Source laobc
In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
Prismatic Groovy Concentric Background 2 No Black
Source GDJ
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
Small gradient crosses inside 45-degree boxes, or bigger crosses if you will.
Source Wassim
A gray background pattern with a texture of textile. Suits perfectly for web design.
Source V. Hartikainen
A seamless light gray paper texture with horizontal double lines.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
A car pattern?! Can it be subtle? I say yes!
Source Radosław Rzepecki
Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This is a seamless pattern of regular hexagon which has a honeycomb structure.
Source Yamachem
Inspired by a drawing in 'Kulturgeschichte', Freidrich Hellwald, 1896.
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin