Prepared mostly as a raster in Paint.net and vectorised.
Source Firkin
A seamless background pattern of dark brown wood planks.
Source V. Hartikainen
More carbon fiber for your collections. This time in white or semi-dark gray.
Source Badhon Ebrahim
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
A classic dark tile for a bit of vintage darkness.
Source Listvetra
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
A green background pattern with warped vertical stripes and a grunge look.
Source V. Hartikainen
An abstract web texture of a polished blue stone (or does it look more like ice).
Source V. Hartikainen
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
Prismatic Polka Dots Mark II 2 No Background
Source GDJ
Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
Prismatic Geometric Pattern Background 2 No Black
Source GDJ
Has nothing to do with toast, but it’s nice and subtle.
Source Pippin Lee
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
Farmer could be some sort of fabric pattern, with a hint of green.
Source Fabian Schultz
A free seamless background pattern for use on websites.
Source V. Hartikainen