From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Number 3 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
Super subtle indeed, a medium gray pattern with tiny dots in a grid.
Source Designova
Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
Like the name says, light and gray, with some small dots and circles.
Source Brenda Lay
A seamless pattern formed from background pattern 102
Source Firkin
A good starting point for a cardboard pattern. This would work well in a variety of colors.
Source Atle Mo
The Grid. A digital frontier. I tried to picture clusters of information as they traveled through the computer.
Source Haris Šumić
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern of "sewn stripes" colored in light gray.
Source V. Hartikainen
Three shades of gray makes this pattern look like a small carbon fiber surface. Great readability even for small fonts.
Source Atle Mo
Formed by distorting an image on Pixabay that was uploaded by gustavorezende. To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Background formed from the original with an emboss effect
Source GDJ
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
One more brick pattern. A bit more depth to this one.
Source Benjamin Ward
Geometric triangles seem to be quite hot these days.
Source Pixeden
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Dark blue concrete wall with some small dust spots.
Source Atle Mo