A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
The original enhanced with some gradients.
Source Firkin
This pattern comes in orange, and it looks as if it is "made of glass".
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Sharp but soft triangles in light shades of gray.
Source Pixeden
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
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 tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Medium gray fabric pattern with 45-degree lines going across.
Source Atle Mo
Number 5 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Remixed from a raster on Pixabay that was uploaded by ArtsyBee.
Source Firkin
Remixed from a drawing in 'Kulturgeschichte der Deutschen im Mittelalter' Franz von Loeher, 1891. The unit tile can be had by selecting the rectangle in Inkscape and using shift-alt-i
Source Firkin
A seamless stone-like background for blogs or any other type of websites.
Source V. Hartikainen
It’s an egg, in the form of a pattern. This really is 2012.
Source Paul Phönixweiß
Remixed from a drawing in 'Works. Popular edition', John Ruskin, 1886.
Source Firkin
A new take on the black linen pattern. Softer this time.
Source Atle Mo
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A pale orange background pattern with glossy groove stripes.
Source V. Hartikainen
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
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
A series of 5 patterns. That’s what the P stands for, if you didn’t guess it.
Source Dima Shiper
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A repeating background with wood/straw like texture.
Source V. Hartikainen