Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
Nothing like a clean set of bed sheets, huh?
Source Badhon Ebrahim
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Zero CC tileable Laminate wood texture, photographed and made by me. CC0
Source Sojan Janso
Zero CC tillable hard cover red book with X shape marks. Scanned and made by me.
Source Sojan Janso
A browner version of the original weathered fence texture.
Source Firkin
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
He influenced us all. “Don’t be sad because it’s over. Smile because it happened.”
Source Atle Mo
White little knobs, coming in at 10x10px. Sweet!
Source Amos
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
Sounds like something from World of Warcraft. Has to be good.
Source Tony Kinard
Prismatic Geometric Pattern Background 2 No Black
Source GDJ
Pattern formed from simple shapes. Black version.
Source Firkin
Free tiled background with colorful stripes and white splatter.
Source V. Hartikainen
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
Alternative colour scheme to the original.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
From an image on opengameart.org shared by rubberduck.
Source Firkin
A free pink background pattern.
Source V. Hartikainen