A seamless pattern made from the gold Penrose triangle by GDJ and the two remixes
Source Firkin
This background pattern contains a seamless texture of bark. It's not very realistic, but I think it looks quite nice.
Source V. Hartikainen
Light and tiny, just the way you like it.
Source Rohit Arun Rao
The Grid. A digital frontier. I tried to picture clusters of information as they traveled through the computer.
Source Haris Šumić
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
This is a seamless pattern of regular hexagon which has a honeycomb structure.
Source Yamachem
Prismatic Isometric Cube Wireframe Pattern No Background
Source GDJ
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
A new one called white wall, not by me this time.
Source Yuji Honzawa
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
Classy golf-pants pattern, or crossed stripes if you will.
Source Will Monson
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin