A cute x, if you need that sort of thing.
Source Juan Scrocchi
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
The tile can be had by selecting the rectangle in Inkscape and using shift+alt+i. Remixed from a drawing in 'Flowers of Song', Frederick Weatherly, 1895.
Source Firkin
Like the name suggests, this background image consists of a pattern of dark bricks. It may be an option for you, if you are looking for something that looks like a brick wall for use as a background on web pages. It's not a masterpiece, but looks pretty nice when is tiled.
Source V. Hartikainen
A free green background pattern with a pattern of rhombuses on a seamless texture. Feel free to use it as a tiled background image on your web site.
Source V. Hartikainen
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
The image depicts a seamless pattern of a Japanese family crest called "chidori" in Japanese .A chidori in Japanese means a plover in English.
Source Yamachem
A seamless dark leather-like background texture with diagonal lines that look like stitches.
Source V. Hartikainen
An alternative colour scheme for the original background.
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
Prismatic Curved Diamond Pattern 5 No Background
Source GDJ
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Zero CC bark from fur tree tileable texture, photographed and made by me. CC0
Source Sojan Janso
Derived from an image that was uploaded to Pixabay by starchim01
Source Firkin
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
It’s an egg, in the form of a pattern. This really is 2012.
Source Paul Phönixweiß
To celebrate the new feature, we need some sparkling diamonds.
Source Atle Mo
Your eyes can trip a bit from looking at this – use it wisely.
Source Michal Chovanec
Based on an image that was uploaded to Pixabay by devanath
Source Firkin
A repeating background with wood/straw like texture.
Source V. Hartikainen
A textured blue background pattern with vertical stripes.
Source V. Hartikainen
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk