The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
A seamless pattern formed from a rectangular tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A dark brown fabric-like background texture with seamless pattern of winding stripes.
Source V. Hartikainen
From a drawing in 'Friend or Fortune? The story of a strange year', Robert Overton, 1897.
Source Firkin
Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Here's a tile-able wood background image for use in web design.
Source V. Hartikainen
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
Remixed from a drawing in 'Canadian forest industries July-December', 1915
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso