You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
Orange-red pattern for tiled backgrounds.
Source V. Hartikainen
From a drawing of the coat of arms of the Ottoman Empire on Wikimedia.
Source Firkin
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
You were craving more leather, so I whipped this up by scanning a leather jacket.
Source Atle Mo
You guessed it – looks a bit like cloth.
Source Peax Webdesign
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
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
Prismatic Geometric Pattern Background 2
Source GDJ
Brushed aluminum, in a bright gray version. Lovely 2X as well.
Source Andre Schouten
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
A repeating background of beige paper with vintage look. Repeats to infinity, as usual.
Source V. Hartikainen
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
This background pattern has futuristic look. So, maybe it could be used on websites or blogs dedicated to video games?!
Source V. Hartikainen
Prismatic Groovy Concentric Background 2
Source GDJ
This one is amazing, truly original. Go use it!
Source Viahorizon
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
You know, tiny and sharp. I’m sure you’ll find a use for it.
Source Atle Mo
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
There are many carbon patterns, but this one is tiny.
Source Designova
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin