A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
Prismatic Groovy Concentric Background 3
Source GDJ
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
Prismatic Abstract Line Art Pattern Background 2
Source GDJ
This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
Very dark pattern with some noise and 45-degree lines.
Source Stefan Aleksić
Remixed from a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
Derived from an image that was uploaded to Pixabay by TheDigitalArtist
Source Firkin
Lovely pattern with some good-looking non-random noise lines.
Source Zucx
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A dark brown fabric-like background texture with seamless pattern of winding stripes.
Source V. Hartikainen
Abstract Tiled Background Extended 12
Source GDJ
8 by 8 pixels, and just what the title says.
Source pixilated
Did anyone say The Hoff? This pattern is in no way related to Baywatch.
Source Josh Green