This one is something special. I’d call it a flat pattern, too. Very well done, sir!
Source GetDiscount
Stefan is hard at work, this time with a funky pattern of squares.
Source Stefan Aleksić
Prismatic Geometric Pattern Background
Source GDJ
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
A bit of scratched up grayness. Always good.
Source Dmitry
A grayscale fabric pattern with vertical lines of stitch holes.
Source V. Hartikainen
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
One more updated pattern. Not really carbon fiber, but it’s the most popular pattern, so I’ll give you an extra choice.
Source Atle Mo
Drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
A rusty grunge background for websites. Feel free to use it in your site's theme.
Source V. Hartikainen
Remixed from a drawing in 'A Girl in Ten Thousand', Elizabeth Meade, 1896.
Source Firkin
Here's a new gray "fabric" pattern. Use it as backgrounds for websites or for other purposes.
Source V. Hartikainen
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
The image depicts a seamless pattern of the design which includes a stylized lotus and a stylized crane.I referred to the original image in a book which is into public domain.
Source Yamachem
This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
Prismatic Curved Diamond Pattern No Background
Source GDJ
A large (588x375px) sand-colored pattern for your ever-growing collection. Shrink at will.
Source Alex Tapein
Prismatic Polka Dots 3 No Background
Source GDJ
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective