This background pattern contains a seamless texture of bark. It's not very realistic, but I think it looks quite nice.
Source V. Hartikainen
Redrawn based on a drawing in 'По Сѣверо-Западу Россіи' Konstantin Sluchevsky, 1897.
Source Firkin
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
Derived from a drawing in 'The Murmur of the Shells', Samuel Cowen, 1879.
Source Firkin
The image depicts a tiled seamless pattern.The tile represents four leaves aligned every 90 ° , which may look like a bird or a dragon .The original leaf design is from a Japanese old book.
Source Yamachem
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Zero CC Mossy stone tileable texture, photographed and made by me. CC0
Source Sojan Janso
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Have you wondered about how it feels to be buried alive? Here is the pattern for it.
Source Hendrik Lammers
Just like the black maze, only in light gray. Duh.
Source Peax
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
The name alone is awesome, but so is this sweet dark pattern.
Source Federica Pelzel
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
A light brushed aluminum pattern for your pleasure.
Source Tim Ward