Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
This one is quite simple in design, it consists of vertical stripes layered on top of a seamless texture.
Source V. Hartikainen
Some more diagonal lines and noise, because you know you want it.
Source Atle Mo
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
Prismatic Abstract Background Design
Source GDJ
Prismatic Floral Pattern 3 Variation 3 No Background
Source GDJ
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Groovy Concentric Background 5 No Black
Source GDJ
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
You guessed it – looks a bit like cloth.
Source Peax Webdesign
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
From a drawing in 'From Snowdon to the Sea. Striking stories of North and South Wales', Marie Trevelyan, 1895.
Source Firkin
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
Free tiled background with colorful stripes and white splatter.
Source V. Hartikainen
A lot of people like the icon patterns, so here’s one for your restaurant blog.
Source Andrijana Jarnjak
A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ