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
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Tile available in Inkscape using shift-alt-i on the selected rectangle
Source Firkin
A free grid paper background pattern for using on web sites.
Source V. Hartikainen
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra
Abstract Tiled Background Extended 12
Source GDJ
Black paper texture, based on two different images.
Source Atle Mo
Based from Design Kindle
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
An aged paper background tile with smeared and pressed text.
Source V. Hartikainen
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Remixed from a drawing in 'Canadian forest industries July-December', 1915
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Zero CC tileable yellow craft paper; scanned and made by me. CC0
Source Sojan Janso
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Here's a seamless brown cork board background texture. Feel free to download or reshare if you like.
Source V. Hartikainen
Nice and simple crossed lines in dark gray tones.
Source Stefan Aleksić
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien