There are many carbon patterns, but this one is tiny.
Source Designova
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
Greyscale version of a pattern that came out of playing with the 'slinky' plug-in for Paint.net
Source Firkin
Abstract Tiled Background Extended 12
Source GDJ
Textured Red Brown Plastic, Free Background Pattern. Although there's already enough plastic in our lives, let's bring it to the web too.)
Source V. Hartikainen
Redrawn based on a drawing in 'По Сѣверо-Западу Россіи' Konstantin Sluchevsky, 1897.
Source Firkin
A free seamless background image with a texture of dark red "canvas". It should look very nice on web sites.
Source V. Hartikainen
Derived from a drawing in 'Elfrica. An historical romance of the twelfth century', Charlotte Boger, 1885
Source Firkin
Here is a new seamless wood texture for using as blog or website backgrounds.
Source V. Hartikainen
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
If you don’t like cream and pixels, you’re in the wrong place.
Source Mizanur Rahman
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
A free grid paper background pattern for using on web sites.
Source V. Hartikainen
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
From a drawing in 'Heroes of North African Discovery', Nancy Meugens, 1894.
Source Firkin
The tile can be had by using shift+alt+i on the selected rectangle in Inkscape
Source Firkin
An abstract pale yellow paper-like background with stains colored in yellow and green.
Source V. Hartikainen
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i
Source Firkin