From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Used the 6th circle pattern designed by Viscious-Speed to create a print that can be used for card making or scrapbooking. Save as a PDF file for the best printing option.
Source Lovinglf
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
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
A heavy hitter at 400x400px, but lovely still.
Source Breezi
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
Prismatic 3D Isometric Tessellation Pattern 6
Source GDJ
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Kaleidoscope Prismatic Abstract No Background
Source GDJ
Different from the original in being a simple tile stored as a pattern definition, rather than numerous repeated objects. Hence easy and quick to give this pattern to objects of different shapes. To get the tile in Inkscape, select the rectangle and use shift+alt+i.
Source Firkin
One more brick pattern. A bit more depth to this one.
Source Benjamin Ward
This is a hot one. Small, sharp and unique.
Source GraphicsWall
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.
Source Paul Phönixweiß
Like the name says, light and gray, with some small dots and circles.
Source Brenda Lay
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
Remixed from a drawing that was uploaded to Pixabay by DavidZydd
Source Firkin
Looks as if it's spray painted on the wall. You can be sure that this pattern will seamlessly fill your backgrounds on web pages.
Source V. Hartikainen