A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
A pale orange background pattern with glossy groove stripes.
Source V. Hartikainen
Prismatic Abstract Geometric Background derived from an image on Pixabay.
Source GDJ
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
Dark blue concrete wall with some small dust spots.
Source Atle Mo
Number 5 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
This seamless web background texture looks like gray stone. It's great for using as a background image on web pages, or on some of their elements. Anyway, I hope you will find use for it.
Source V. Hartikainen
The classic notebook paper with horizontal stripes.
Source Are Sundnes
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
Remixed from an image on Pixabay, the original having been uploaded by darkmoon1968.
Source Firkin
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf