Lovely pattern with splattered vintage speckles.
Source David Pomfret
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A background pattern with blue on white vertical stripes.
Source V. Hartikainen
The classic subtle pattern. Sort of wall/brick looking. Or moon-looking?
Source Joel Klein
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
I’m starting to think I have a concrete wall fetish.
Source Atle Mo
More bright luxury. This is a bit larger than fancy deboss, and with a bit more noise.
Source Viszt Péter
Hey, you never know when you’ll need a bird pattern, right?
Source Pete Fecteau
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
Here I have tried to create something that would look like maple wood. Not sure how well it's turned out, but at least it looks like wood.
Source V. Hartikainen
Fabric-ish patterns are close to my heart. French Stucco to the rescue.
Source Christopher Buecheler
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
Based on an image that was uploaded to Pixabay by devanath
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Light honeycomb pattern made up of the classic hexagon shape.
Source Federica Pelzel
Dark Tile-able Grunge Texture. I think this texture can be classified as grunge. It's free and seamless, as always.
Source V. Hartikainen
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Here's a camo print with more tan and less green, such as might be used in a desert scenario. This is tileable, so it can be used as a wallpaper or background.
Source Eady
Prismatic Groovy Concentric Background 3
Source GDJ
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective