A pattern drawn in Paint.net and vectorized in Inkscape.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Prismatic Geometric Pattern Background 2
Source GDJ
A pale yellow background pattern with vertical stripes. The stripes are partially faded. I think this background image turned out pretty well, especially those faded stripes.
Source V. Hartikainen
A car pattern?! Can it be subtle? I say yes!
Source Radosław Rzepecki
Sweet and subtle white plaster with hints of noise and grunge.
Source Phil Maurer
CC0 and seamless wellington boot pattern.
Source SliverKnight
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
Alternative colour scheme for the original floral pattern.
Source Firkin
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Formed by distorting an image on Pixabay that was uploaded by gustavorezende. To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
Prismatic Groovy Concentric Background 2 No Black
Source GDJ
A bit of scratched up grayness. Always good.
Source Dmitry
One more brick pattern. A bit more depth to this one.
Source Benjamin Ward
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Utilising a bird from s-light and some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
A seamless pattern with green and yellow diagonal lines on top of a white dotted background.
Source V. Hartikainen