I took the liberty of using Dmitry’s pattern and made a version without perforation.
Source Atle Mo
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
Different from the original in being a simple tile stored as a pattern definition, rather than numerous repeated objects. Hence easy and quick to give this pattern to objects of different shapes. To get the tile in Inkscape, select the rectangle and use shift+alt+i.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Old China with a modern twist, take two.
Source Adam Charlts
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
An abstract texture of water. It's not perfect, but will do. You may download if you like it.
Source V. Hartikainen
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
Derived from an image that was uploaded to Pixabay by starchim01
Source Firkin
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
This one is amazing, truly original. Go use it!
Source Viahorizon
A bit strange this one, but nice at the same time.
Source Diogo Silva
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
Fake or not, it’s quite luxurious.
Source Factorio.us Collective
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Lovely pattern with splattered vintage speckles.
Source David Pomfret
A cute x, if you need that sort of thing.
Source Juan Scrocchi
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
I love the movie Pineapple Express, and I’m also liking this Pineapple right here.
Source Audee Mirza
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin