A comeback for you: the popular Escheresque, now in black.
Source Patten
This one is amazing, truly original. Go use it!
Source Viahorizon
A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Remixed from a drawing in 'Line and form", Walter Crane, 1914.
Source Firkin
Bright gray tones with a hint of some metal surface.
Source Hendrik Lammers
Floral patterns will never go out of style, so enjoy this one.
Source Lasma
Seamless Background For Websites. It has a texture similar to cork-board.
Source V. Hartikainen
This is a hot one. Small, sharp and unique.
Source GraphicsWall
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Vertical lines with a bumpy, yet crisp, feel to it.
Source Raasa
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
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
A large pattern with funky shapes and form. An original. Sort of origami-ish.
Source Luuk van Baars
Prismatic Geometric Tessellation Pattern No Background
Source GDJ
Derived from an image that was uploaded to Pixabay by starchim01
Source Firkin
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
From a drawing in 'Uit de geschiedenis der Heilige Stede te Amsterdam', Yohannes Sterck, 1898.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Greyscale version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin