A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Groovy Concentric Background
Source GDJ
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
This one is amazing, truly original. Go use it!
Source Viahorizon
The starting point for this was drawn on the web site steamcoded.org/PolyskelionMaker.svg
Source Firkin
The basic shapes never get old. Simple triangle pattern.
Source Atle Mo
This one needs to be used in small areas; you can see it repeat.
Source Luca
Background formed from the original with an emboss effect
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i
Source Firkin
A seamless pattern formed from background pattern 102
Source Firkin
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Geometric Pattern Background 2 No Black
Source GDJ
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media
More leather, and this time it’s bigger! You know, in case you need that.
Source Elemis
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
Love the style on this one, very fresh. Diagonal diamond pattern. Get it?
Source INS
Zero CC tileable hard cover cells book texture, 4k, scanned and made by me. CC0
Source Sojan Janso