In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
Very simple, very blu(e). Subtle and nice.
Source Seb Jachec
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
Light gray version of the Binding pattern that looks a bit like fabric.
Source Newbury
Black brick wall pattern. Brick your site up!
Source Alex Parker
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Remixed from a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Pattern Background, Texture, Photoshop Structure style CC0 texture.
Source Darkmoon1968
Same classic 45-degree pattern, dark version.
Source Luke McDonald
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A cute x, if you need that sort of thing.
Source Juan Scrocchi
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Prismatic Groovy Concentric Background 2
Source GDJ
Another fairly simple design drawn in Paint.net and vectorized in Inkscape.
Source Firkin