A free black metallic background pattern. Here's a new pattern I made that looks metallic.
Source V. Hartikainen
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless pattern of leopard skin. It should look nice as a background element on web pages.
Source V. Hartikainen
A seamlessly tileable pink background texture.
Source V. Hartikainen
From a drawing in 'Codogno e il suo territorio nella cronaca e nella storia'', Gio and Giarella Cairo, 1897.
Source Firkin
Prismatic Groovy Concentric Background No Black
Source GDJ
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
Vector version of a JPG that was uploaded to Pixabay by theasad121
Source Firkin
A seamless web texture of "green stone".
Source V. Hartikainen
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
It’s like Shine Dotted’s sister, only rotated 45 degrees.
Source mediumidee
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous
From a drawing in 'Bond Slaves. The story of a struggle.', Isabella Varley, 1893.
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
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin