Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Some more diagonal lines and noise, because you know you want it.
Source Atle Mo
The name alone is awesome, but so is this sweet dark pattern.
Source Federica Pelzel
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
A lot of people like the icon patterns, so here’s one for your restaurant blog.
Source Andrijana Jarnjak
Alternative colour scheme for the original floral pattern.
Source Firkin
I have no idea what J Boo means by this name, but hey – it’s hot.
Source j Boo
A seamless pattern formed from a tile made from ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Dark Tile-able Grunge Texture. I think this texture can be classified as grunge. It's free and seamless, as always.
Source V. Hartikainen
Alternative colour scheme for the original floral pattern.
Source Firkin
Background formed from the original with an emboss effect
Source GDJ
Here's a dark background pattern that contains a steel grid pattern as a texture. Use it as a website background or for other purposes. It's free!
Source V. Hartikainen
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A white version of the very popular linen pattern.
Source Ant Ekşiler
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
An alternative colour scheme to the original seamless pattern.
Source Firkin
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
Prismatic Abstract Geometric Background 4
Source GDJ