From an image on opengameart.org shared by rubberduck.
Source Firkin
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
Prismatic Polka Dots Mark II 3 No Background
Source GDJ
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
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
Abstract Tiled Background Extended 10
Source GDJ
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
This is sort of fresh, but still feels a bit old school.
Source Martuchox
No, not the band but the pattern. Simple squares in gray tones, of course.
Source Atle Mo
Sharp diamond pattern. A small 24x18px tile.
Source Tom Neal
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
This background image has seamless texture that resembles a surface of gray stone.
Source V. Hartikainen
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Prismatic Abstract Geometric Background 4
Source GDJ
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
Awesome name, great pattern. Who does not love space?
Source Nick Batchelor
A repeating background with a look of paper. I have added some changes to PatCreator. Now you can share your designs by submitting them to a new gallery section. Start by clicking Edit with PatCreator above.
Source V. Hartikainen
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A seamless striped fabric-like texture colored in a dark reddish brown color.
Source V. Hartikainen
From a drawing in 'Hubert Montreuil, or the Huguenot and the Dragoon', Francisca Ouvry, 1873.
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. A version of the original with random colors.
Source Firkin
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper