A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.
Source V. Hartikainen
Zero CC tileable brick texture, photographed and made by me. CC0
Source Sojan Janso
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
Prismatic Curved Diamond Pattern No Background
Source GDJ
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
A pattern drawn in Paint.net and vectorized in Inkscape.
Source Firkin
Vertical lines with a bumpy, yet crisp, feel to it.
Source Raasa
Formed by distorting an image on Pixabay that was uploaded by gustavorezende. To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
More carbon fiber for your collections. This time in white or semi-dark gray.
Source Badhon Ebrahim
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Not the Rebel alliance, but a dark textured pattern.
Source Hendrik Lammers
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Derived from a corner decoration itself found as a jpg on Pixabay.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
Square design drawn in Paint.net and vectorized in Vector Magic.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
A re-make of the Gradient Squares pattern.
Source Dimitar Karaytchev
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
Sort of reminds me of those old house wallpapers.
Source Tish
The name tells you it has curves. Oh yes, it does!
Source Peter Chon
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova