This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Tile available in Inkscape using shift-alt-i on the selected rectangle
Source Firkin
Prismatic Polyskelion Pattern No Background
Source GDJ
The name is totally random, but hey, it sounds good.
Source Atle Mo
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
From an image on opengameart.org shared by rubberduck.
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Dark wooden pattern, given the subtle treatment. based on texture from Cloaks.
From a drawing in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
This one resembles a black concrete wall when is tiled. It should look great, at least with dark website themes.
Source V. Hartikainen
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee