If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
So tiny, just 7 by 7 pixels – but still so sexy. Ah yes.
Source Dmitriy Prodchenko
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Pattern Background, Texture, Photoshop Structure style CC0 texture.
Source Darkmoon1968
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Nice and simple crossed lines in dark gray tones.
Source Stefan Aleksić
Dark Tile-able Grunge Texture. I think this texture can be classified as grunge. It's free and seamless, as always.
Source V. Hartikainen
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Nicely crafted paper pattern, although a bit on the large side (500x593px).
Source Blaq Annabiosis
Submitted by DomainsInfo – wtf, right? But hey, a free pattern.
Source DomainsInfo
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
Clover with background for St. Patrick's Day. Add to a card with a doily, ribbon, a leprechaun or other embellishments.
Source BAJ
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
You know, tiny and sharp. I’m sure you’ll find a use for it.
Source Atle Mo