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
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
I have no idea what J Boo means by this name, but hey – it’s hot.
Source j Boo
Seamless SVG vector and JPG backgrounds with faded diagonal stripes. The colors are editable.
Source V. Hartikainen
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Inspired by a drawing seen in 'City of Liverpool', James Picton, 1883.
Source Firkin
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
A bit strange this one, but nice at the same time.
Source Diogo Silva
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
White handmade paper pattern with small bumps.
Source Marquis
Sometimes you just need the simplest thing.
Source Fabricio
A seamless pattern formed from a tile made from page ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.
Source Atle Mo
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
Lovely pattern with some good-looking non-random noise lines.
Source Zucx
An abstract web texture of a polished blue stone (or does it look more like ice).
Source V. Hartikainen
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A dark pattern made out of 3×3 circles and a 1px shadow. This works well as a carbon texture or background.
Source Atle Mo
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Zero CC tileable grass texture, photographed and made by me. CC0
Source Sojan Janso
This background has abstract texture with some similarities to wood.
Source V. Hartikainen
CC0 and seamless wellington boot pattern.
Source SliverKnight