Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
Bit of a strange name on this one, but still nice. Tiny gray square things.
Source Carlos Valdez
A very dark spotted twinkle pattern for your twinkle needs.
Source Badhon Ebrahim
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Formed by distorting a JPG from PublicDomainPictures
Source Firkin
Derived from a drawing in 'Historiske Afhandlinger', Adolf Jorgensen, 1898.
Source Firkin
A version without colours blended together to give a different look.
Source Firkin
A new one called white wall, not by me this time.
Source Yuji Honzawa
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Prismatic Groovy Concentric Background 3
Source GDJ
Fabric-ish patterns are close to my heart. French Stucco to the rescue.
Source Christopher Buecheler
Prismatic Abstract Background Design No Black
Source GDJ
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
More in the paper realm, this time with fibers.
Source Jorge Fuentes
The tile for this is based on a repeating unit close to a design on Pixabay. It can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A brown seamless wood texture in a form of stripe pattern. The result has turned out pretty well, in my opinion.
Source V. Hartikainen
A seamless paper background colored in pale yellow.
Source V. Hartikainen
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
A light background pattern with diagonal stripes. Here's a simple light striped background for you.
Source V. Hartikainen
Prismatic Abstract Line Art Pattern Background
Source GDJ
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Colour version of the original pattern inspired by the front cover of 'Old and New Paris', Henry Edwards, 1894.
Source Firkin
A seamless background pattern with impressed gray dots.
Source V. Hartikainen
This is a semi-dark pattern, sort of linen-y.
Source Sagive SEO