As far as fabric patterns goes, this is quite crisp.
Source Heliodor Jalba
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Seamless Background For Websites. It has a texture similar to cork-board.
Source V. Hartikainen
A seamless background tile of aged paper with shabby look.
Source V. Hartikainen
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
He influenced us all. “Don’t be sad because it’s over. Smile because it happened.”
Source Atle Mo
A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Everyone needs some stardust. Sprinkle it on your next project.
Source Atle Mo
Prismatic Curved Diamond Pattern 5 No Background
Source GDJ
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
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
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Pattern produced in Paint.net using the Vibrato plug-in.
Source Firkin
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
Colour version of the original pattern.
Source Firkin