This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Kaleidoscope Prismatic Abstract No Background
Source GDJ
A seamless light gray paper texture with horizontal double lines.
Source V. Hartikainen
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
Just the symbols of the signs of the zodiac distributed in a chequer board-like pattern
Source Firkin
Seamless pattern formed from a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Not so subtle. These tileable wood patterns are very useful.
Source Elemis
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
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
Prismatic Geometric Tessellation Pattern 3 No Background
Source GDJ
A seamless pattern of "sewn stripes" colored in light gray.
Source V. Hartikainen
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin