From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Prismatic Geometric Pattern Background 2
Source GDJ
This is a grid, only it’s noisy. You know. Reminds you of those printed grids you draw on.
Source Vectorpile
Seamless Prismatic Quadrilateral Line Art Pattern No Background
Source GDJ
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
Lovely pattern with some good-looking non-random noise lines.
Source Zucx
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A yellow tiled background... Blurriness, bokeh effect and rectangles pattern in one mix.
Source V. Hartikainen
Prismatic Groovy Concentric Background No Black
Source GDJ
A series of 5 patterns. That’s what the P stands for, if you didn’t guess it.
Source Dima Shiper
Alternative colour scheme for the original floral pattern.
Source Firkin
From a drawing in 'Picturesque New Guinea', J Lindt, 1887.
Source Firkin
Derived from a drawing in 'The Murmur of the Shells', Samuel Cowen, 1879.
Source Firkin
More carbon fiber for your collections. This time in white or semi-dark gray.
Source Badhon Ebrahim
Prismatic Abstract Line Art Pattern Background 2
Source GDJ
A free background pattern with abstract green tiles.
Source V. Hartikainen
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
That’s what it is, a dark dot. Or sort of carbon looking.
Source Tsvetelin Nikolov
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo