Derived from a corner decoration itself found as a jpg on Pixabay.
Source Firkin
Same classic 45-degree pattern, dark version.
Source Luke McDonald
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
Three shades of gray makes this pattern look like a small carbon fiber surface. Great readability even for small fonts.
Source Atle Mo
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
Classic vertical lines, in all its subtlety.
Source Cody L
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
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
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
Abstract Geometric Monochrome Pattern Prismatic No Background
Source GDJ
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
From a drawing in 'Heroes of North African Discovery', Nancy Meugens, 1894.
Source Firkin