Here I have tried to create something that would look like maple wood. Not sure how well it's turned out, but at least it looks like wood.
Source V. Hartikainen
From a drawing in 'Hundert Jahre in Wort und Bild', S. Stefan, 1899.
Source Firkin
A version without colours blended together to give a different look.
Source Firkin
Black & white version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
A seamless light gray paper texture with horizontal double lines.
Source V. Hartikainen
Here's a tile-able wood background image for use in web design.
Source V. Hartikainen
Alternative colour scheme. 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
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
Prismatic Groovy Concentric Background 5
Source GDJ
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan