Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
The image is a design of blue glass.How about using it as background image?
Source Yamachem
There are many carbon patterns, but this one is tiny.
Source Designova
Derived from a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Inspired by the B&O Play, I had to make this pattern.
Source Atle Mo
Nicely crafted paper pattern, although a bit on the large side (500x593px).
Source Blaq Annabiosis
Geometric triangles seem to be quite hot these days.
Source Pixeden
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Prismatic Groovy Concentric Background
Source GDJ
Seamless Prismatic Quadrilateral Line Art Pattern No Background
Source GDJ
Imagine you zoomed in 1000X on some fabric. But then it turned out to be a skeleton!
Source Angelica
A free black metallic background pattern. Here's a new pattern I made that looks metallic.
Source V. Hartikainen
Black brick wall pattern. Brick your site up!
Source Alex Parker
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Groovy Concentric Background No Black
Source GDJ