The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
The following repeating website background is colored in a blue gray color and resembles a concrete wall or something similar to it.
Source V. Hartikainen
A re-make of the Gradient Squares pattern.
Source Dimitar Karaytchev
Inspired by a drawing seen in 'City of Liverpool', James Picton, 1883.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
This seamless light brown background texture resembles a wallpaper with vertical stripes. One way to use it is as a tiled background on web sites.
Source V. Hartikainen
Classic vertical lines, in all its subtlety.
Source Cody L
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
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Derived from a design in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin
Dead simple but beautiful horizontal line pattern.
Source Fabian Schultz
Prismatic Curved Diamond Pattern 5 No Background
Source GDJ
Remixed from a PNG that was uploaded to Pixabay by gingertea
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
A repeating background of thick textured paper. Actually, it turned out to look like something between a paper and fabric.
Source V. Hartikainen
Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
This one is amazing, truly original. Go use it!
Source Viahorizon
A new take on the black linen pattern. Softer this time.
Source Atle Mo
Someone was asking about how to achieve a fur pattern at #inkscape irc so tried to make a filter on it. Flood filled fractal noises rigged together. May someone find a good use for these.
Source Lazur URH
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
CC0 remixed from a drawing. Walter Crane, 1914, Firkin.
Source SliverKnight
Zero CC tileable cork floor, photographed and made by me. CC0
Source Sojan Janso