Might not be super subtle, but quite original in its form.
Source Alex Smith
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
Semi-light fabric pattern made out of random pixels in shades of gray.
Source Atle Mo
Prismatic Groovy Concentric Background 3
Source GDJ
The image depicts a seamless pattern of a snow crystal.I referred to a book called ”sekka-zusetsu” or "雪華図説" which means an illustrated explanation about snow crystals.This book was published in 1832 (天保3年) or Edo period.For more about "雪華図説",see here:dl.ndl.go.jp/info:ndljp/pid/2536975
Source Yamachem
Found on the ground in french cafe in kunming, Yunnan, china
Source Rejon
Green Web Background, Seamless tile.
Source V. Hartikainen
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
You know you love wood patterns, so here’s one more.
Source Richard Tabor
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
Prismatic Geometric Pattern Background 2 No Black
Source GDJ
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
No relation to the band, but damn it’s subtle!
Source Thomas Myrman
It’s a hole, in a pattern. On your website. Dig it!
Source Josh Green
A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
CC0 remixed from a drawing. Walter Crane, 1914, Firkin.
Source SliverKnight
Prismatic Groovy Concentric Background 3
Source GDJ