Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
From a drawing in 'La Principauté de Liège et les Pays-Bas au XVIe siècle', Société des Bibliophiles Liégeois ,1887.
Source Firkin
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
Zero CC tileable pine bark texture, photographed and made by me. CC0
Source Sojan Janso
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
There are quite a few grid patterns, but this one is a super tiny grid with some dust for good measure.
Source Dominik Kiss
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Sort of like the back of a wooden board. Light, subtle, and stylish, just the way we like it!
Source Nikolalek
From a drawing in 'Gately's World's Progress', Charles Beale, 1886.
Source Firkin
Prismatic Abstract Geometric Background 5 No Black
Source GDJ
Medium gray fabric pattern with 45-degree lines going across.
Source Atle Mo