Dark, crisp and subtle. Tiny black lines on top of some noise.
Source Wilmotte Bastien
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
Embossed lines and squares with subtle highlights.
Source Alex Parker
This one needs to be used in small areas; you can see it repeat.
Source Luca
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
From a drawing in 'A Rolling Stone. A tale of wrongs and revenge', John Hartley, 1878.
Source Firkin
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
A cute x, if you need that sort of thing.
Source Juan Scrocchi
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
I scanned a paper coffee cup. You know, in case you need it.
Source Atle Mo
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
The following repeating website background is colored in a blue gray color and resembles a concrete wall or something similar to it.
Source V. Hartikainen
Light gray paper pattern with small traces of fiber and some dust.
Source Atle Mo
Remixed from a drawing in 'Some account of the Worshipful Company of Ironmongers', John Nicholl, 1866.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Feel free to download this "Dark Wood" background texture for your web site. The background tiles seamlessly!
Source V. Hartikainen
Found on the ground in french cafe in kunming, Yunnan, china
Source Rejon
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
Non-seamless pattern drawn in Paint.net and vectorised in Vector Magic.
Source Firkin