Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Similar to original, but without gaps in between the arrows. This seamless pattern was created from a rectangular tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Dark blue concrete wall with some small dust spots.
Source Atle Mo
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Like the name says, light and gray, with some small dots and circles.
Source Brenda Lay
One can never have too few rice paper patterns, so here is one more.
Source Atle Mo
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
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Alternative colour scheme for the original floral pattern.
Source Firkin
Formed by distorting a JPG from PublicDomainPictures
Source Firkin
This one is super crisp at 2X. Lined paper with some dust and scratches.
Source HQvectors
A free seamless background with pink spots.
Source V. Hartikainen
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
From a drawing in 'Cassell's Library of English Literature', Henry Morley, 1883.
Source Firkin
Never out of fashion and so much hotter than the 45º everyone knows, here is a sweet 60º line pattern.
Source Atle Mo
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
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae