Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
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
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
You were craving more leather, so I whipped this up by scanning a leather jacket.
Source Atle Mo
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
A seamless pattern with green and yellow diagonal lines on top of a white dotted background.
Source V. Hartikainen
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
Prismatic Polyskelion Pattern No Background
Source GDJ
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
Prismatic Triangular Seamless Pattern III With Background
Source GDJ
A pattern drawn in Paint.net and vectorized in Vector Magic.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
This one is amazing, truly original. Go use it!
Source Viahorizon
Here's an yet another seamless note paper texture for use as a background on websites.
Source V. Hartikainen
Formed from decorative divider 184 in paint.net. Vectorised with Vector Magic.
Source Firkin
A seamless texture of a rough concrete surface.
Source V. Hartikainen
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
A seamlessly tileable pink background texture.
Source V. Hartikainen
The name is totally random, but hey, it sounds good.
Source Atle Mo
The image depicts a shell seamless pattern.I used an OCAL clipart called "Shell" uploaded by "jgm104".Thanks.
Source Yamachem