A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
From a drawing in 'Kingsdene', Maria Fetherstonehaugh, 1878.
Source Firkin
A pale orange background pattern with glossy groove stripes.
Source V. Hartikainen
A pattern derived from part of a fractal rendering in Paint.net.
Source Firkin
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
Formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
There are many carbon patterns, but this one is tiny.
Source Designova
Fix and cc0 to get the tile this is based on.
Source SliverKnight
Inspired by the B&O Play, I had to make this pattern.
Source Atle Mo
Tweed is back in style – you heard it here first. Also, the @2X version here is great!
Source Simon Leo
Retro Circles Background 8 No Black
Source GDJ
A classic dark tile for a bit of vintage darkness.
Source Listvetra
Have you wondered about how it feels to be buried alive? Here is the pattern for it.
Source Hendrik Lammers
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Have you wondered about how it feels to be buried alive? Here is the pattern for it.
Source Hendrik Lammers
Colour version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin