Might not be super subtle, but quite original in its form.
Source Alex Smith
Sweet and subtle white plaster with hints of noise and grunge.
Source Phil Maurer
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A seamless pattern of "sewn stripes" colored in light gray.
Source V. Hartikainen
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
If you don’t like cream and pixels, you’re in the wrong place.
Source Mizanur Rahman
A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
Number 3 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Prismatic Abstract Geometric Background 4
Source GDJ
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
This light blue background pattern is quite pleasing to the eye, it consists of a tiny rough grid pattern, which is seamless by design. That's it, if you like the color, you can use this seamless pattern in a web design without making any further modifications to it.
Source V. Hartikainen
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
Zero CC tileable dry grass texture, photographed and made by me. CC0
Source Sojan Janso
I love cream! 50x50px and lovely in all the good ways.
Source Thomas Myrman
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
This seamless background image should look nice on websites. It has a dark blue gray texture with vertical stripes, it tiles seamlessly and, like all of the background images here, it's free. So, if you like it, take it!
Source V. Hartikainen
Prismatic Polka Dots Mark II 3 No Background
Source GDJ
This was formed by distorting an image of a background on Pixabay.
Source Firkin
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper