Vector version of a JPG that was uploaded to Pixabay by theasad121
Source Firkin
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Prismatic Polyskelion Pattern No Background
Source GDJ
To get the tile this is based on 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
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
The image is a seamless pattern of a fishnet.
Source Yamachem
Number five from the same submitter, makes my job easy.
Source Dima Shiper
Super dark, crisp and detailed. And a Kill Bill reference.
Source Badhon Ebrahim
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
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Subtle scratches on a light gray background.
Source Andrey Ovcharov
A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.
Source V. Hartikainen
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Derived from an image that was uploaded to Pixabay by darkmoon1968
Source Firkin
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
Prismatic Floral Pattern 3 Variation 3 No Background
Source GDJ
A seamless texture of a rough concrete surface.
Source V. Hartikainen
Inspired by a 1930s wallpaper pattern I saw on TV.
Source Firkin
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
Prismatic Floral Background No Black
Source GDJ
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin