Not so subtle. These tileable wood patterns are very useful.
Source Elemis
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This is the remix of "blue wave-seigaiha".The image depicts a seamless pattern of the front upper part of Japanese five yen coin which is used currently.This design represents a rice with ripe golden ears.
Source Yamachem
Super dark, crisp and detailed. And a Kill Bill reference.
Source Badhon Ebrahim
Retro Circles Background 4 No Black
Source GDJ
Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
Background Wall, Art Abstract, Watercolor Vintage style CC0 texture.
Source Ractapopulous
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Just like the black maze, only in light gray. Duh.
Source Peax
This white background pattern has a seamless grunge style texture. Here's a white grunge style background pattern. Use it as a tiled background image on web sites or for other purposes.
Source V. Hartikainen
A seamless pattern formed from background pattern 102
Source Firkin
Prismatic Basic Pattern 2 No Background
Source GDJ
I love these crisp, tiny, super subtle patterns.
Source Badhon Ebrahim
Prismatic Curved Diamond Pattern 3 No Background
Source GDJ
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
A seamless pattern formed from a modified version of rwwgub's tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Love the style on this one, very fresh. Diagonal diamond pattern. Get it?
Source INS
A seamless pattern formed from a tile made from page ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Formed from decorative divider 184 in paint.net. Vectorised with Vector Magic.
Source Firkin
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
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
A seamless light gray paper texture with horizontal double lines.
Source V. Hartikainen
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne