Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
This is a hot one. Small, sharp and unique.
Source GraphicsWall
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
Sharp pixel pattern, just like the good old days.
Source Paridhi
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
This background pattern contains a texture of yellow wood planks. I think it looks quite original.
Source V. Hartikainen
A dark pattern made out of 3×3 circles and a 1px shadow. This works well as a carbon texture or background.
Source Atle Mo
You know I love paper patterns. Here is one from Stephen. Say thank you!
Source Stephen Gilbert
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Same as Silver Scales, but in black. Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
Colour version of the original pattern inspired by the front cover of 'Old and New Paris', Henry Edwards, 1894.
Source Firkin
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
You guessed it – looks a bit like cloth.
Source Peax Webdesign