This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Geometric Tessellation Pattern 2 No Background
Source GDJ
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
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Zero CC Mossy stone tileable texture, photographed and made by me. CC0
Source Sojan Janso
The classic notebook paper with horizontal stripes.
Source Are Sundnes
A seamless pattern the starting point for which was a 'light rays' rendering in Paint.net.
Source Firkin
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
I took the liberty of using Dmitry’s pattern and made a version without perforation.
Source Atle Mo
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Remixed from a drawing that was uploaded to Pixabay by ractapopulous
Source Firkin
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
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Subtle scratches on a light gray background.
Source Andrey Ovcharov
Old China with a modern twist, take two.
Source Adam Charlts
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Here's a brown background pattern with subtle stripes. I hope you'll like the color. If not, feel free to change it using an image editor, if you know how of course. Personally, I'm using GIMP to create these backgrounds.
Source V. Hartikainen
Prismatic Groovy Concentric Background 3
Source GDJ
Mostly just mucked about with the colours and made one of the paths in the lead frame opaque. The glass remains transparent.
Source Firkin