All good things come in threes, so I give you the third in my little concrete wall series.
Source Atle Mo
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
Small gradient crosses inside 45-degree boxes, or bigger crosses if you will.
Source Wassim
A free seamless background image with a texture of dark red "canvas". It should look very nice on web sites.
Source V. Hartikainen
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
The image a seamless pattern derived from a weed which I can't identify.The original weed image is from here:https://jp.pinterest.com/pin/500744052301423641/
Source Yamachem
Sharp pixel pattern, just like the good old days.
Source Paridhi
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
f you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Derived from an image that was uploaded to Pixabay by TheDigitalArtist
Source Firkin
Prismatic Floral Pattern 3 Variation 3 No Background
Source GDJ
The basic shapes never get old. Simple triangle pattern.
Source Atle Mo
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
Subtle scratches on a light gray background.
Source Andrey Ovcharov
From a drawing in 'Friend or Fortune? The story of a strange year', Robert Overton, 1897.
Source Firkin
Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
Zero CC tileable wood texture, made by me procedurally in Neo Texture Edit.
Source Sojan Janso
A dark metallic background with a pattern of stamped dots. Here's a dark "metallic" background pattern for you.
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
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin