A seamless background pattern with impressed gray dots.
Source V. Hartikainen
The image depicts polka dot seamless pattern.
Source Yamachem
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
Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
To celebrate the new feature, we need some sparkling diamonds.
Source Atle Mo
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A car pattern?! Can it be subtle? I say yes!
Source Radosław Rzepecki
A seamless background pattern with a texture of wood planks. This wood background pattern has vertically arranged planks. You may try to rotate it 90°, to see how it will look like when the wood planks are arranged horizontally.
Source V. Hartikainen
Prismatic Polka Dots 3 No Background
Source GDJ
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.
Source Simon Meek
A colourful background drawn originally in paint.net and vectorised in Vector Magic.
Source Firkin
A dark background pattern/texture of a dimpled metal plate.
Source V. Hartikainen
Background formed from the original with an emboss effect.
Source Firkin
Farmer could be some sort of fabric pattern, with a hint of green.
Source Fabian Schultz
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts