A comeback for you: the popular Escheresque, now in black.
Source Patten
Black paper texture, based on two different images.
Source Atle Mo
Based from Design Kindle
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
This yellow background consists of a pattern of glossy gold buttons arranged in polka dot style on a seamless texture. Here's a pale yellow background pattern. Feel free to use it for your needs!
Source V. Hartikainen
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
An alternative colour scheme for the original seamless texture formed from an image on Pixabay.
Source Firkin
A seamless green background texture. The image is distributed under a Creative Commons License (like all of the images here).
Source V. Hartikainen
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin
A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
Heavily remixed from a drawing in 'Barbara Leybourne; a story of eighty years ago', Sarah Hamer, 1889.
Source Firkin
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
This is the remix of an Openclipart clipart called "Maze" uploaded by "any_ono_mous".Thanks.This is a seamless pattern of a maze.
Source Yamachem
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
A large pattern with funky shapes and form. An original. Sort of origami-ish.
Source Luuk van Baars
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media
More carbon fiber for your collections. This time in white or semi-dark gray.
Source Badhon Ebrahim
Prismatic Abstract Geometric Background 5
Source GDJ
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
Fake or not, it’s quite luxurious.
Source Factorio.us Collective