A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Prismatic Triangular Background Design Mark II 5
Source GDJ
Remixed from a drawing that was uploaded to Pixabay by DavidZydd
Source Firkin
Remixed from a drawing in 'Line and form", Walter Crane, 1914.
Source Firkin
Fake or not, it’s quite luxurious.
Source Factorio.us Collective
Abstract Ellipses Background Grayscale
Source GDJ
So tiny, just 7 by 7 pixels – but still so sexy. Ah yes.
Source Dmitriy Prodchenko
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
A seamless dark leather-like background texture with diagonal lines that look like stitches.
Source V. Hartikainen
Wild Oliva or Oliva Wilde? Darker than the others, sort of a medium dark pattern.
Source Badhon Ebrahim
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
Zero CC tileable Crackled Cement (streaks) texture, photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Here's a seamless brown cork board background texture. Feel free to download or reshare if you like.
Source V. Hartikainen
A car pattern?! Can it be subtle? I say yes!
Source Radosław Rzepecki
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
This yellow background consists of a pattern of glossy gold buttons arranged in polka dot style on a seamless texture. Here's a pale yellow background pattern. Feel free to use it for your needs!
Source V. Hartikainen
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin