A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
One more sharp little tile for you. Subtle circles this time.
Source Blunia
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Hey, you never know when you’ll need a bird pattern, right?
Source Pete Fecteau
Green Web Background, Seamless tile.
Source V. Hartikainen
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
This one could be the shirt of a golf player. Angled lines in different thicknesses.
Source Olivier Pineda
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Can never have too many knitting patterns, especially as nice as this.
Source Victoria Spahn
A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
Formed by distorting an image on Pixabay that was uploaded by gustavorezende. To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
By popular request, an outline version of the pentagon pattern.
Source Atle Mo
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
Classic vertical lines, in all its subtlety.
Source Cody L
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
This was submitted in a beige color, hence the name. Now it’s a gray paper pattern.
Source Konstantin Ivanov
Abstract Tiled Background Extended 11
Source GDJ
A classic dark tile for a bit of vintage darkness.
Source Listvetra
One more sharp little tile for you. Subtle circles this time.
Source Blunia
CC0 remixed from a drawing. Walter Crane, 1914, Firkin.
Source SliverKnight