Not the Rebel alliance, but a dark textured pattern.
Source Hendrik Lammers
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
The name is totally random, but hey, it sounds good.
Source Atle Mo
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Prismatic Hexagonalism Pattern No Background
Source GDJ
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
From a drawing in 'An Old Maid's Love. A Dutch tale told in English', Maarten Maartens, 1891.
Source Firkin
A dark metal plate with an embossed grid pattern and a bit of rust. Here's a dark metal plate texture for use as a tiled background on web pages.
Source V. Hartikainen
A comeback for you: the popular Escheresque, now in black.
Source Patten
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Dark wooden pattern, given the subtle treatment. based on texture from Cloaks.
Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern
Source Firkin
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
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
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Prismatic Rounded Squares Grid 4 No Background
Source GDJ
The original enhanced with some gradients.
Source Firkin
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
Prismatic Rounded Squares Grid 3 No Background
Source GDJ