Some rectangles, a bit of dust and grunge, plus a hint of concrete.
Source Atle Mo
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Green Web Background, Seamless tile.
Source V. Hartikainen
I have no idea how to describe this one, but it’s light and delicate.
Source JBasoo
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
Colour version of the original pattern.
Source Firkin
A pale olive green background with a seamless texture.
Source V. Hartikainen
Retro Circles Background 4 No Black
Source GDJ
I love these crisp, tiny, super subtle patterns.
Source Badhon Ebrahim
This was formed by distorting an image of a background on Pixabay.
Source Firkin
A seamless striped fabric-like texture colored in a dark reddish brown color.
Source V. Hartikainen
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Medium gray fabric pattern with 45-degree lines going across.
Source Atle Mo
A floral background formed from numerous clones of flower 117.
Source Firkin
Prismatic Abstract Background Design
Source GDJ
A free background pattern with abstract green tiles.
Source V. Hartikainen
You were craving more leather, so I whipped this up by scanning a leather jacket.
Source Atle Mo
A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.
Source V. Hartikainen
Produced using the clouds, flames and glass blocks plug-ins in Paint.net and the resulting .PNG vectorised with Vector Magic.
Source Firkin
You know I love paper patterns. Here is one from Stephen. Say thank you!
Source Stephen Gilbert
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight