A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Uses spirals from Pixabay. To get the basic tile select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
White circles connecting on a light gray background.
Source Mark Collins
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
Prismatic Hexagonalism Pattern No Background
Source GDJ
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
This is a hot one. Small, sharp and unique.
Source GraphicsWall
Vector version of a JPG that was uploaded to Pixabay by theasad121
Source Firkin
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
A series of 5 patterns. That’s what the P stands for, if you didn’t guess it.
Source Dima Shiper
Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
A free grid paper background pattern for using on web sites.
Source V. Hartikainen
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin