A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A simple but elegant classic. Every collection needs one of these.
Source Christopher Burton
Uses spirals from Pixabay. To get the basic tile select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin
I took the liberty of using Dmitry’s pattern and made a version without perforation.
Source Atle Mo
A seamless canvas texture for using as background on websites. Colored in pale tones of brown.
Source V. Hartikainen
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
You were craving more leather, so I whipped this up by scanning a leather jacket.
Source Atle Mo
A white version of the very popular linen pattern.
Source Ant Ekşiler
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim
Drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Prismatic Polka Dots Mark II 2 No Background
Source GDJ
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
8 by 8 pixels, and just what the title says.
Source pixilated
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
New paper pattern with a slightly organic feel to it, using some thin threads.
Source Atle Mo