Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Prismatic Curved Diamond Pattern 5 No Background
Source GDJ
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Fix and cc0 to get the tile this is based on.
Source SliverKnight
Zero CC tileable hard cover red book, scanned and made by me. CC0
Source Sojan Janso
Prismatic Geometric Tessellation Pattern 3 No Background
Source GDJ
Remixed from a JPG that was uploaded to Pixabay by susanlu4esm
Source Firkin
A seamless pattern formed from background pattern 102
Source Firkin
Remixed from a drawing that was uploaded to Pixabay by DavidZydd
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
A free seamless background pattern for use on websites.
Source V. Hartikainen
He influenced us all. “Don’t be sad because it’s over. Smile because it happened.”
Source Atle Mo
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
A very slick dark rubber grip pattern, sort of like the grip on a camera.
Source Sinisha
That’s what it is, a dark dot. Or sort of carbon looking.
Source Tsvetelin Nikolov
Colour version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
Prismatic Hexagonalism Pattern No Background
Source GDJ
A repeatable image with dark background and metal grid pattern.
Source V. Hartikainen
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
A repeating background with a look of paper. I have added some changes to PatCreator. Now you can share your designs by submitting them to a new gallery section. Start by clicking Edit with PatCreator above.
Source V. Hartikainen
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin