Looks like an old rug or a computer chip.
Source Patutin Sergey
Prismatic Abstract Line Art Pattern Background 2
Source GDJ
Same as the black version, but now in shades of gray. Very subtle and fine grained.
Source Atle Mo
From a drawing in 'A Guide to the Guildhall of the City of London', John Baddeley, 1898.
Source Firkin
A very dark spotted twinkle pattern for your twinkle needs.
Source Badhon Ebrahim
Derived from a JPG that was uploaded to Pixabay by ractapopulous
Source Firkin
A version without colours blended together to give a different look.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
Very simple, very blu(e). Subtle and nice.
Source Seb Jachec
I love cream! 50x50px and lovely in all the good ways.
Source Thomas Myrman
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Inspired by this, I came up with this pattern. Madness!
Source Atle Mo
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
A background pattern with a look of rough fabric.
Source V. Hartikainen
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
Abstract Ellipses Background Grayscale
Source GDJ
With a name like this, it has to be hot. Diagonal lines in light shades.
Source Isaac