People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
Formed by distorting a JPG from PublicDomainPictures
Source Firkin
Prismatic Geometric Pattern Background No Black
Source GDJ
Zero CC tileable hard cover cells, skin like, book texture. 4K, Scanned and made by me CC0
Source Sojan Janso
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
Black brick wall pattern. Brick your site up!
Source Alex Parker
It’s big, it’s gradient—and it’s square.
Source Brankic1979
Background Wall, Art Abstract, Watercolor Vintage style CC0 texture.
Source Ractapopulous
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
It’s like Shine Dotted’s sister, only rotated 45 degrees.
Source mediumidee
Some rectangles, a bit of dust and grunge, plus a hint of concrete.
Source Atle Mo
Abstract Tiled Background Extended 8
Source GDJ
A repeating gloomy background image. This one consists of a pattern of black chains layered on top of a dark textured background.
Source V. Hartikainen
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Otis Ray Redding was an American soul singer-songwriter, record producer, arranger, and talent scout. So you know.
Source Thomas Myrman
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Black And White Floral Pattern Background from PDP.
Source GDJ
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
Prismatic Hexagonalism Pattern No Background
Source GDJ
Sharp pixel pattern, just like the good old days.
Source Paridhi
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
A free seamless background texture that looks like a brown stone wall.
Source V. Hartikainen