A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
Derived from a drawing in 'Historiske Afhandlinger', Adolf Jorgensen, 1898.
Source Firkin
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
A gray background pattern with a texture of textile. Suits perfectly for web design.
Source V. Hartikainen
Not the Rebel alliance, but a dark textured pattern.
Source Hendrik Lammers
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Black & white version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
Utilising a bird from s-light and some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
This background pattern contains a texture of yellow wood planks. I think it looks quite original.
Source V. Hartikainen
Prismatic Geometric Pattern Variation 2 With Background
Source GDJ
A nice looking light gray background pattern with diagonal stripes.
Source V. Hartikainen
All good things come in threes, so I give you the third in my little concrete wall series.
Source Atle Mo
Prismatic Geometric Tessellation Pattern No Background
Source GDJ
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
8 by 8 pixels, and just what the title says.
Source pixilated
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
Remixed from a drawing in 'Очерки Русской Исторіи въ памятникахъ быта', Petr Polevoi, 1879.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
Prismatic Triangular Background Design Mark II 5
Source GDJ