This one is so simple, yet so good. And you know it. Has to be in the collection.
Source Gluszczenko
This is a remix of "blue wave-seigaiha".I hope this subtle color version of Seigaiha would be suitable for background .
Source Yamachem
From an image on opengameart.org shared by rubberduck.
Source Firkin
Here's a brown background pattern with subtle stripes. I hope you'll like the color. If not, feel free to change it using an image editor, if you know how of course. Personally, I'm using GIMP to create these backgrounds.
Source V. Hartikainen
Embossed lines and squares with subtle highlights.
Source Alex Parker
Brushed aluminum, in a bright gray version. Lovely 2X as well.
Source Andre Schouten
Sharp diamond pattern. A small 24x18px tile.
Source Tom Neal
The Grid. A digital frontier. I tried to picture clusters of information as they traveled through the computer.
Source Haris Šumić
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Abstract Tiled Background Extended 10
Source GDJ
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
Prismatic Groovy Concentric Background
Source GDJ
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
This is a seamless pattern of regular hexagon which has a honeycomb structure.
Source Yamachem
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
You know, tiny and sharp. I’m sure you’ll find a use for it.
Source Atle Mo
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin