Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Number five from the same submitter, makes my job easy.
Source Dima Shiper
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
Tile-able Dark Brown Wood Background. Feel free to use it as a background image in your designs or somewhere on the web. By the way, the color seems to be close to Coffee Brown.
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
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
From a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Inspired by a drawing in 'Kulturgeschichte', Freidrich Hellwald, 1896.
Source Firkin
This background pattern looks like bamboo to me. Feel free to download it for your website (for your blog perhaps?).
Source V. Hartikainen
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
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 seamless texture of worn out "cardboard".
Source V. Hartikainen
A free green background pattern with a pattern of rhombuses on a seamless texture. Feel free to use it as a tiled background image on your web site.
Source V. Hartikainen
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
This metal background pattern resembles a metal plate with rivets. Solid rivets on a metal plate.
Source V. Hartikainen
Imagine you zoomed in 1000X on some fabric. But then it turned out to be a skeleton!
Source Angelica
A seamless green background texture. The image is distributed under a Creative Commons License (like all of the images here).
Source V. Hartikainen