A free background image with a seamless texture of cardboard. This texture of cardboard looks quite realistic, especially when is actually tiled.
Source V. Hartikainen
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Formed by distorting a JPG from PublicDomainPictures
Source Firkin
Based on an image that was uploaded to Pixabay by devanath
Source Firkin
Sounds like something from World of Warcraft. Has to be good.
Source Tony Kinard
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A seamless tessellation pattern. To get the tile this is formed from, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A new take on the black linen pattern. Softer this time.
Source Atle Mo
This one is so simple, yet so good. And you know it. Has to be in the collection.
Source Gluszczenko
A seamless green background texture. The image is distributed under a Creative Commons License (like all of the images here).
Source V. Hartikainen
A beautiful dark wood pattern, superbly tiled.
Source Omar Alvarado
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
Prismatic Geometric Pattern Background
Source GDJ