Might not be super subtle, but quite original in its form.
Source Alex Smith
A rusty grunge background for websites. Feel free to use it in your site's theme.
Source V. Hartikainen
Looks like an old rug or a computer chip.
Source Patutin Sergey
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
From drawing in 'Musings in Maoriland', Thomas Bracken, 1890.
Source Firkin
Derived from an image that was uploaded to Pixabay by TheDigitalArtist
Source Firkin
8 by 8 pixels, and just what the title says.
Source pixilated
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
You may use it as is, or modify it as you like.
Source V. Hartikainen
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Prismatic Rounded Squares Grid 3 No Background
Source GDJ
Remixed from a drawing in 'Paul's Sister', Frances Peard, 1889.
Source Firkin
This is sort of fresh, but still feels a bit old school.
Source Martuchox
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
Here is a new seamless wood texture for using as blog or website backgrounds.
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin