This is lovely, just the right amount of subtle noise, lines and textures.
Source Richard Tabor
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A seamless web texture with illustration of pale color stains on canvas.
Source V. Hartikainen
Drawn in Paint.net and vectorised in Vector Magic
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Just the symbols of the signs of the zodiac distributed in a chequer board-like pattern
Source Firkin
From a drawing in 'Az Osztrák-Magyar Monarchia irásban és képben', 1885.
Source Firkin
An abstract pale yellow paper-like background with stains colored in yellow and green.
Source V. Hartikainen
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
A very dark asfalt pattern based off of a photo taken with my iPhone.
Source Atle Mo
I guess this is inspired by the city of Ravenna in Italy and its stone walls.
Source Sentel
This is a grid, only it’s noisy. You know. Reminds you of those printed grids you draw on.
Source Vectorpile
A black tile-able background with paper-like texture.
Source V. Hartikainen
Tile available in Inkscape using shift-alt-i on the selected rectangle
Source Firkin
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
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
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Here's a camo print with more tan and less green, such as might be used in a desert scenario. This is tileable, so it can be used as a wallpaper or background.
Source Eady