Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
This seamless background image should look nice on websites. It has a dark blue gray texture with vertical stripes, it tiles seamlessly and, like all of the background images here, it's free. So, if you like it, take it!
Source V. Hartikainen
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
Here's a dark background pattern that contains a steel grid pattern as a texture. Use it as a website background or for other purposes. It's free!
Source V. Hartikainen
One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
Here's a subtle marble-like background for use on websites.
Source V. Hartikainen
Geometric triangles seem to be quite hot these days.
Source Pixeden
From a drawing in 'La Principauté de Liège et les Pays-Bas au XVIe siècle', Société des Bibliophiles Liégeois ,1887.
Source Firkin
This background pattern contains a seamless texture of bark. It's not very realistic, but I think it looks quite nice.
Source V. Hartikainen
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
A dark background pattern/texture of a dimpled metal plate.
Source V. Hartikainen
Zero CC tileable dry grass texture, photographed and made by me. CC0
Source Sojan Janso
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Has nothing to do with toast, but it’s nice and subtle.
Source Pippin Lee
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
Looks like an old wall. I guess that’s it then?
Source Viahorizon
A seamless pattern of leopard skin. It should look nice as a background element on web pages.
Source V. Hartikainen
Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.
Source Simon Meek
The name tells you it has curves. Oh yes, it does!
Source Peter Chon
Scanned some rice paper and tiled it up for you. Enjoy.
Source Atle Mo