Fix side and a seamless pattern formed from circles.
Source SliverKnight
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
This one resembles a black concrete wall when is tiled. It should look great, at least with dark website themes.
Source V. Hartikainen
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
Prismatic Snowflakes Pattern No Background
Source GDJ
Real snow that tiles, not easy. This is not perfect, but an attempt.
Source Atle Mo
A seamless pattern of leopard skin. It should look nice as a background element on web pages.
Source V. Hartikainen
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Background formed from the original with an emboss effect
Source GDJ
Here's a subtle marble-like background for use on websites.
Source V. Hartikainen
Mostly just mucked about with the colours and made one of the paths in the lead frame opaque. The glass remains transparent.
Source Firkin
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Abstract Tiled Background Extended 6
Source GDJ
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Zero CC tileable moss or lichen covered stone texture, edited from pixabay. CC0
Source Sojan Janso
The name is totally random, but hey, it sounds good.
Source Atle Mo
Abstract Tiled Background Extended 8
Source GDJ
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin