Zero CC bark from fur tree tileable texture, photographed and made by me. CC0
Source Sojan Janso
Honestly, who does not like a little pipe and mustache?
Source Luca Errico
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
The image depicts a seamless pattern of a Japanese family crest called "chidori" in Japanese .A chidori in Japanese means a plover in English.
Source Yamachem
Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Number 5 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
The base gradient edited so now more details are rendered.
Source Lazur URH
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
This is a semi-dark pattern, sort of linen-y.
Source Sagive SEO
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Looks like an old rug or a computer chip.
Source Patutin Sergey
Number 4 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
Black version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
A background pattern with green vertical stripes. A new striped background pattern. This time a green one.
Source V. Hartikainen