From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Scanned some rice paper and tiled it up for you. Enjoy.
Source Atle Mo
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Prismatic Groovy Concentric Background 3
Source GDJ
Prismatic Triangular Background Design Mark II 5
Source GDJ
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
A brown seamless wood texture in a form of stripe pattern. The result has turned out pretty well, in my opinion.
Source V. Hartikainen
Prismatic Abstract Background Design No Black
Source GDJ
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Polka Dots Mark II No Background
Source GDJ
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Light gray pattern with an almost wall tile-like appearance.
Source Markus Tinner
This is indeed a bit strange, but here’s to the crazy ones!
Source Christopher Buecheler
The starting point for this was drawn on the web site steamcoded.org/PolyskelionMaker.svg
Source Firkin
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
Super detailed 16×16 tile that forms a beautiful pattern of straws.
Source Pavel