A comeback for you: the popular Escheresque, now in black.
Source Patten
This is so subtle I hope you can see it! Tweak at will.
Source Alexandre Naud
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
The image depicts a seamless pattern of a Japanese family crest called "chidori" in Japanese .A chidori in Japanese means a plover in English.
Source Yamachem
Just the symbols of the signs of the zodiac distributed in a chequer board-like pattern
Source Firkin
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A simple circle. That’s all it takes. This one is even transparent, for those who like that.
Source Saqib
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless pattern formed from a square tile based on a jpg on Pixabay. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
A set of paper filters. The base texture is generated the same way, only the compositing mode is varied.
Source Lazur URH
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
Prismatic Abstract Geometric Background 5
Source GDJ
Formed by distorting a JPG from PublicDomainPictures
Source Firkin
Light and tiny, just the way you like it.
Source Rohit Arun Rao
One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Remixed from an image on Pixabay, the original having been uploaded by darkmoon1968.
Source Firkin