If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
An abstract web texture of a polished blue stone (or does it look more like ice).
Source V. Hartikainen
One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
CC0 remixed from a drawing. Walter Crane, 1914, Firkin.
Source SliverKnight
The Grid. A digital frontier. I tried to picture clusters of information as they traveled through the computer.
Source Haris Šumić
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Used in small doses, this could be a nice subtle pattern. Used on a large surface, it’s dirty!
Source Paul Reulat
The texture of this background image has some similarities with leather, and it's colored in a dark brown color. So, if you are looking for a dark brown background image for your website, this may be an option for you.
Source V. Hartikainen
A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
The image is a seamless pattern of a fishnet.
Source Yamachem
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Has nothing to do with toast, but it’s nice and subtle.
Source Pippin Lee
One more brick pattern. A bit more depth to this one.
Source Benjamin Ward
Same as the black version, but now in shades of gray. Very subtle and fine grained.
Source Atle Mo
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
This one is super crisp at 2X. Lined paper with some dust and scratches.
Source HQvectors
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
A cute x, if you need that sort of thing.
Source Juan Scrocchi
A blue gray fabric-like texture for websites. An yet another fabric-like texture. It has subtle vertical and diagonal stripes to it.
Source V. Hartikainen