Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
Remixed from a JPG that was uploaded to Pixabay by susanlu4esm
Source Firkin
Inspired by a 1930s wallpaper pattern I saw on TV.
Source Firkin
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
The image depicts a seamless pattern of a Japanese family crest called "chidori" in Japanese .A chidori in Japanese means a plover in English.
Source Yamachem
A bit strange this one, but nice at the same time.
Source Diogo Silva
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf
Prismatic Geometric Pattern Background 2 No Black
Source GDJ
A dark gray, sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.
Source Firkin
There are quite a few grid patterns, but this one is a super tiny grid with some dust for good measure.
Source Dominik Kiss
emixed from a JPG that was uploaded to Pixabay by Kyotime
Source Firkin
An abstract texture of black metal pipes (seamless).
Source V. Hartikainen