More in the paper realm, this time with fibers.
Source Jorge Fuentes
A comeback for you: the popular Escheresque, now in black.
Source Patten
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.
Source Nathan Spady
Abstract Tiled Background Extended 12
Source GDJ
From a drawing in 'Kingsdene', Maria Fetherstonehaugh, 1878.
Source Firkin
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
A seamlessly tileable pink background texture.
Source V. Hartikainen
A free seamless background with pink spots.
Source V. Hartikainen
Prismatic Isometric Cube Wireframe Pattern No Background
Source GDJ
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
From an image on opengameart.org shared by rubberduck.
Source Firkin