A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
A pale orange background pattern with glossy groove stripes.
Source V. Hartikainen
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
Zero CC tileable Laminate wood texture, photographed and made by me. CC0
Source Sojan Janso
Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From a drawing in 'Artists and Arabs', Henry Blackburn, 1868
Source Firkin
Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern
Source Firkin
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
Background pattern originally a PNG drawn in Paint.net
Source Firkin
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
Green Background Pattern
Source V. Hartikainen
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Abstract Tiled Background Extended 12
Source GDJ
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
Adapted from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
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