Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
Prismatic Triangular Background Design Mark II 5
Source GDJ
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
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
Prismatic Polka Dots Mark II 3 No Background
Source GDJ
Colour version that is close to the original drawing uploaded to Pixabay by pencilparker.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A seamless pattern created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
Derived from a drawing in 'Historiske Afhandlinger', Adolf Jorgensen, 1898.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
A seamless texture of black leather. I think it will look best when used in headers, footers or sidebars.
Source V. Hartikainen
The image a seamless pattern of a wire-mesh fence.I want you to use this pattern as a lower layer.
Source Yamachem
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
A gray background pattern with a texture of textile. Suits perfectly for web design.
Source V. Hartikainen
Subtle scratches on a light gray background.
Source Andrey Ovcharov
Pattern Background, Texture, Photoshop Structure style CC0 texture.
Source Darkmoon1968
Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.
Source Simon Meek