Not so subtle. These tileable wood patterns are very useful.
Source Elemis
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
Inspired by a JPG that was uploaded to Pixabay by kokon_art
Source Firkin
The texture of this background image has some similarities with leather, and it's colored in a dark brown color. So, if you are looking for a dark brown background image for your website, this may be an option for you.
Source V. Hartikainen
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Abstract Tiled Background Extended 12
Source GDJ
This one is amazing, truly original. Go use it!
Source Viahorizon
A pale orange background pattern with glossy groove stripes.
Source V. Hartikainen
An abstract web texture of a polished blue stone (or does it look more like ice).
Source V. Hartikainen
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.
Source Paul Phönixweiß
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
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
Prismatic Abstract Line Art Pattern Background
Source GDJ
A bit strange this one, but nice at the same time.
Source Diogo Silva
Remixed from a vector adapted from a jpg on Pixabay. The tile this is constructed from can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
Inspired by an image that was uploaded to Pixabay by geralt
Source Firkin
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Seamless pattern inspired by a drawing on Pixabay. To get the tile this is formed from, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prepared mostly as a raster in Paint.net and vectorised.
Source Firkin