Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
A seamless pattern drawn originally in Paint.net by distorting a slice of background pattern 116 and copying the resulting triangle numerous times.
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
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
Colour version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
A seamless background of warped stripes on paper.
Source V. Hartikainen
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Prismatic Geometric Pattern Background 2
Source GDJ
A seamless pattern created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
A repeating background for websites with a texture of black groove stripes.
Source V. Hartikainen
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin