Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
The image depicts a seamless pattern of Japanese Edo pattern called "kikkou-matsu" or "亀甲松" meaning " tortoiseshell-pinetree".The real pinetree is like this: https://jp.pinterest.com/pin/500744052301065077/
Source Yamachem
A seamless pattern made from the gold Penrose triangle by GDJ and the two remixes
Source Firkin
Prismatic Abstract Background Design
Source GDJ
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
Derived from an image that was uploaded to Pixabay by mdmelo.
Source Firkin
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A free seamless background texture of "timber wall" (colored in dark brown).
Source V. Hartikainen
I skipped number 3, because it wasn’t all that great. Sorry.
Source Dima Shiper
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Can never have too many knitting patterns, especially as nice as this.
Source Victoria Spahn
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Remixed from a drawing in 'Some account of the Worshipful Company of Ironmongers', John Nicholl, 1866.
Source Firkin
The original enhanced with one of Inkscapes's filters.
Source Firkin
Vertical lines with a bumpy, yet crisp, feel to it.
Source Raasa