First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.
Source Atle Mo
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A light gray wall or floor (you decide) of concrete.
Source Atle Mo
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern with a unit cell drawn as a bitmap in Paint.net and vectorized in Vector Magic.
Source Firkin
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
Prismatic Groovy Concentric Background
Source GDJ
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
A repeating background with dark brown stone-like texture and abstract pattern that looks like tree trunks.
Source V. Hartikainen
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Have you wondered about how it feels to be buried alive? Here is the pattern for it.
Source Hendrik Lammers
Prismatic Isometric Cube Wireframe Pattern No Background
Source GDJ
Nice and simple crossed lines in dark gray tones.
Source Stefan Aleksić
Your eyes can trip a bit from looking at this – use it wisely.
Source Michal Chovanec
Tiny little flowers growing on your screen. Nice, huh?
Source Themes Tube
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
The basic shapes never get old. Simple triangle pattern.
Source Atle Mo
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett