Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Spice up your next school project with this icon background.
Source Swetha
Seamless Prismatic Geometric Pattern With Background
Source GDJ
This background image has seamless texture that resembles a surface of gray stone.
Source V. Hartikainen
Wasn't satisfied with the original's colouring. Too much component transfer and colormatrixes yet the results are lacking a bit. So this time it is a simple black to transparent fade, making it possible remixing easily once there will be other blending modes supported as well. Probably in inkscape 0.92.
Source Lazur URH
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
The original enhanced with some gradients.
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A seamless pattern of "sewn stripes" colored in light gray.
Source V. Hartikainen
Plywood Web Background background image for use in web design.
Source V. Hartikainen
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
Remixed from a drawing that was uploaded to Pixabay by ractapopulous
Source Firkin
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
Some more diagonal lines and noise, because you know you want it.
Source Atle Mo
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin