Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Prismatic Abstract Geometric Background 5 No Black
Source GDJ
A seamless web texture of "green stone".
Source V. Hartikainen
A very dark spotted twinkle pattern for your twinkle needs.
Source Badhon Ebrahim
A seamless pattern formed from cross 4. To get the original tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Wild Oliva or Oliva Wilde? Darker than the others, sort of a medium dark pattern.
Source Badhon Ebrahim
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
This one needs to be used in small areas; you can see it repeat.
Source Luca
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
You know you love wood patterns, so here’s one more.
Source Richard Tabor
Love the style on this one, very fresh. Diagonal diamond pattern. Get it?
Source INS
From a drawing in 'Cassell's Library of English Literature', Henry Morley, 1883.
Source Firkin
Psychedelic Geometric Background No Black
Source GDJ
Small dots with minor circles spread across to form a nice mosaic.
Source John Burks
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A bit simplified version. Although it could be edited out to be simpler. Anyway, this time the tiling is converted to a pattern fill -which is using clipping for the tile's edges.
Source Lazur URH
From a drawing in 'Hubert Montreuil, or the Huguenot and the Dragoon', Francisca Ouvry, 1873.
Source Firkin
Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.
Source Firkin
Sometimes you just need the simplest thing.
Source Fabricio
Here's a new paper-like background for free use on personal and commercial projects (this applies to all background patterns here).
Source V. Hartikainen
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim