The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
I took the liberty of using Dmitry’s pattern and made a version without perforation.
Source Atle Mo
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
From a drawing in 'Heroes of North African Discovery', Nancy Meugens, 1894.
Source Firkin
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
It’s an egg, in the form of a pattern. This really is 2012.
Source Paul Phönixweiß
A bit of scratched up grayness. Always good.
Source Dmitry
Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.
Source Simon Meek
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Prismatic Hexagonalist Pattern No Background
Source GDJ
Sharp but soft triangles in light shades of gray.
Source Pixeden
CC0 and seamless wellington boot pattern.
Source SliverKnight