This ladies and gentlemen, is texturetastic! Love it.
Source Adam Pickering
Medium gray fabric pattern with 45-degree lines going across.
Source Atle Mo
A comeback for you: the popular Escheresque, now in black.
Source Patten
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A rusty grunge background for websites. Feel free to use it in your site's theme.
Source V. Hartikainen
Thin lines, noise and texture creates this crisp dark denim pattern.
Source Marco Slooten
8 by 8 pixels, and just what the title says.
Source pixilated
This light background pattern has a texture of "frozen" surface with diagonal stripes. Here's an yet another addition to the collection of free website backgrounds.
Source V. Hartikainen
You know you can’t get enough of these linen-fabric-y patterns.
Source James Basoo
Classic vertical lines, in all its subtlety.
Source Cody L
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on 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
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
A very dark asfalt pattern based off of a photo taken with my iPhone.
Source Atle Mo
This is lovely, just the right amount of subtle noise, lines and textures.
Source Richard Tabor
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Heavily remixed from a drawing that was uploaded to Pixabay by ractapopulous
Source Firkin
There are many carbon patterns, but this one is tiny.
Source Designova
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin