I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i. Alternative colour scheme.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
Colour version of the original pattern.
Source Firkin
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
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
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
The image depicts an edo-era pattern called "same-komon" or "鮫小紋"which looks like a shark skin.The "same" in Japanese means shark in English.
Source Yamachem
A seamless pattern with a unit cell drawn as a bitmap in Paint.net and vectorized in Vector Magic.
Source Firkin
Zero CC tileable dry grass texture, photographed and made by me. CC0
Source Sojan Janso
A seamless background tile of aged paper with shabby look.
Source V. Hartikainen
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
Prismatic Hexagonalism Pattern No Background
Source GDJ
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A very dark spotted twinkle pattern for your twinkle needs.
Source Badhon Ebrahim
To get the tile this is based on, 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