In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
Formed from a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Pass parameters to the URL or edit the source code variables to configure the graph paper for the division desired.
Source JayNick
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
Prismatic Geometric Pattern Background No Black
Source GDJ
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
A bit strange this one, but nice at the same time.
Source Diogo Silva
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
Adapted from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Inspired by a pattern I saw in a 19th century book. This seamless pattern was created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
Prismatic Polka Dots Mark II 2 No Background
Source GDJ
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Lovely light gray floral motif with some subtle shades.
Source GraphicsWall
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ