A seamless pattern created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).
Source V. Hartikainen
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
Psychedelic Geometric Background No Black
Source GDJ
Light gray pattern with an almost wall tile-like appearance.
Source Markus Tinner
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
Zero CC tileable brick texture, photographed and made by me. CC0
Source Sojan Janso
First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.
Source Atle Mo
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
It’s an egg, in the form of a pattern. This really is 2012.
Source Paul Phönixweiß
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Little x’es, noise and all the stuff you like. Dark like a Monday, with a hint of blue.
Source Tom McArdle
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
ZeroCC tileable wood boards texture, photographed and made by me. CC0
Source Sojan Janso
Vertical lines with a bumpy, yet crisp, feel to it.
Source Raasa
A dark metallic background with a pattern of stamped dots. Here's a dark "metallic" background pattern for you.
Source V. Hartikainen
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
A new one called white wall, not by me this time.
Source Yuji Honzawa
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran