This background pattern looks like bamboo to me. Feel free to download it for your website (for your blog perhaps?).
Source V. Hartikainen
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
I have no idea what J Boo means by this name, but hey – it’s hot.
Source j Boo
Prismatic Curved Diamond Pattern No Background
Source GDJ
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.
Source Simon Meek
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
Very simple, very blu(e). Subtle and nice.
Source Seb Jachec
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
8 by 8 pixels, and just what the title says.
Source pixilated
Prismatic Basic Pattern 2 No Background
Source GDJ
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
The basic shapes never get old. Simple triangle pattern.
Source Atle Mo
Remixed from a JPG that was uploaded to Pixabay by theasad121
Source Firkin
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
A repeating background of beige paper with vintage look. Repeats to infinity, as usual.
Source V. Hartikainen
This is indeed a bit strange, but here’s to the crazy ones!
Source Christopher Buecheler
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica