A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Prismatic Abstract Geometric Background 4
Source GDJ
Remixed from a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
A repeating background of beige paper with vintage look. Repeats to infinity, as usual.
Source V. Hartikainen
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
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
An abstract Background pattern of purple twisty patterns.
Source TikiGiki
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
A seamless texture of black leather. I think it will look best when used in headers, footers or sidebars.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Prismatic Snowflakes Pattern No Background
Source GDJ
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
A free background image with a seamless texture of cardboard. This texture of cardboard looks quite realistic, especially when is actually tiled.
Source V. Hartikainen
One more from Badhon, sharp horizontal lines making an embossed paper feeling.
Source Badhon Ebrahim
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Utilising a bird from s-light and some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
This is a remix of "blue wave-seigaiha".I hope this subtle color version of Seigaiha would be suitable for background .
Source Yamachem
Clean and crisp lines all over the place. Wrap it up with this one.
Source Dax Kieran
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin