Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Prismatic Groovy Concentric Background 5
Source GDJ
A free seamless background with pink spots.
Source V. Hartikainen
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
A free seamless background texture that looks like a brown stone wall.
Source V. Hartikainen
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
This is a semi-dark pattern, sort of linen-y.
Source Sagive SEO
Prismatic Curved Diamond Pattern 3 No Background
Source GDJ
The image depicts meshed silhouettes of various things.The original image is an OCAL clipart called "Enter FOSSASIA 2016 #IoT T-shirt Design Contest" uploaded by "openclipart".Thanks.
Source Yamachem
Prismatic Abstract Background Design No Black
Source GDJ
Abstract Ellipses Background Grayscale
Source GDJ
I guess this is inspired by the city of Ravenna in Italy and its stone walls.
Source Sentel
Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Colorful Floral Background 3 No Black
Source GDJ
A version without colours blended together to give a different look.
Source Firkin
Tiny circle waves, almost like the ocean.
Source Sagive
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i
Source Firkin