A very slick dark rubber grip pattern, sort of like the grip on a camera.
Source Sinisha
A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.
Source V. Hartikainen
The green fibers pattern will work very well in grayscale as well.
Source Matteo Di Capua
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Dead simple but beautiful horizontal line pattern.
Source Fabian Schultz
Remixed from a drawing in 'Line and form", Walter Crane, 1914.
Source Firkin
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
Adapted from an image that was uploaded to Pixabay by Anerma.
Source Firkin
This texture looks like old leather. It should look great as a background on web pages.
Source V. Hartikainen
A seamless pattern formed from a tile made from page ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Same as the black version, but now in shades of gray. Very subtle and fine grained.
Source Atle Mo
Remixed from a drawing that was uploaded to Pixabay by ractapopulous
Source Firkin
Prismatic Abstract Background Design
Source GDJ
Abstract Ellipses Background Grayscale
Source GDJ
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Snap! It’s a pattern, and it’s not grayscale! Of course you can always change the color in Photoshop.
Source Atle Mo
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
A frame using leaves from an image that was uploaded to Pixabay by mayapujiati
Source Firkin
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
Prismatic Groovy Concentric Background 4 No Black
Source GDJ
The image depicts a seamless pattern of a fishnet with a plenty of fish.It may be a lucky charm for fishermen.
Source Yamachem