A seamless pattern with a unit cell drawn as a bitmap in Paint.net and vectorized in Vector Magic.
Source Firkin
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf
Background pattern made in "Grunge-Like" style. Available in both SVG and JPG formats. Edit to your needs then click the download button.
Source V. Hartikainen
Prismatic Geometric Tessellation Pattern 2 No Background
Source GDJ
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
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
A version without colours blended together to give a different look.
Source Firkin
This is a seamless pattern which is derived from a flower petal image.
Source Yamachem
Actually, there's no clouds in it, but I think it looks quite nice.
Source V. Hartikainen
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
One more sharp little tile for you. Subtle circles this time.
Source Blunia
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I. Version with black background.
Source Firkin
Fake or not, it’s quite luxurious.
Source Factorio.us Collective
A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
A background pattern with a look of rough fabric.
Source V. Hartikainen