The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
Zero CC tileable moss or lichen covered stone texture, edited from pixabay. CC0
Source Sojan Janso
Prismatic Abstract Background Design No Black
Source GDJ
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i
Source Firkin
No, not the band but the pattern. Simple squares in gray tones, of course.
Source Atle Mo
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
This background pattern contains worn out colorful stripes as a texture.
Source V. Hartikainen
The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
Some more diagonal lines and noise, because you know you want it.
Source Atle Mo
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Embossed lines and squares with subtle highlights.
Source Alex Parker
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A dark brown fabric-like background texture with seamless pattern of winding stripes.
Source V. Hartikainen
A white version of the very popular linen pattern.
Source Ant Ekşiler
You were craving more leather, so I whipped this up by scanning a leather jacket.
Source Atle Mo
The image depicts a seamless pattern which includes hexagonally-aligned gourds with BG in light-brown.
Source Yamachem