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
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
The image depicts a seamless pattern of a snow crystal.I referred to a book called ”sekka-zusetsu” or "雪華図説" which means an illustrated explanation about snow crystals.This book was published in 1832 (天保3年) or Edo period.For more about "雪華図説",see here:dl.ndl.go.jp/info:ndljp/pid/2536975
Source Yamachem
Derived from an image that was uploaded to Pixabay by darkmoon1968
Source Firkin
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
Number 2 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
One more from Badhon, sharp horizontal lines making an embossed paper feeling.
Source Badhon Ebrahim
From a drawing in 'Worsborough; its historical associations and rural attractions', Joseph Wilkinson, 1879.
Source Firkin
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
Prismatic Geometric Tessellation Pattern 4 No Background
Source GDJ
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Actually, there's no clouds in it, but I think it looks quite nice.
Source V. Hartikainen
Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
I guess this is inspired by the city of Ravenna in Italy and its stone walls.
Source Sentel
A seamless green background texture. The image is distributed under a Creative Commons License (like all of the images here).
Source V. Hartikainen
A new take on the black linen pattern. Softer this time.
Source Atle Mo
This is lovely, just the right amount of subtle noise, lines and textures.
Source Richard Tabor
To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
A version without colours blended together to give a different look.
Source Firkin
One more from Badhon, sharp horizontal lines making an embossed paper feeling.
Source Badhon Ebrahim