Dark and hard, just the way we like it. Embossed triangles makes a nice pattern.
Source Ivan Ginev
A beautiful dark wood pattern, superbly tiled.
Source Omar Alvarado
From a design in 'Storia del Palazzo Vecchio in Firenze', Aurelio Gotti, 1889.
Source Firkin
This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.
Source Lazur URH
Otis Ray Redding was an American soul singer-songwriter, record producer, arranger, and talent scout. So you know.
Source Thomas Myrman
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
Lovely light gray floral motif with some subtle shades.
Source GraphicsWall
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
A free seamless background image with a texture of dark red "canvas". It should look very nice on web sites.
Source V. Hartikainen
From a drawing in 'Hyde Park from Domesday-Book to date', John Ashton, 1896.
Source Firkin
Number five from the same submitter, makes my job easy.
Source Dima Shiper
You know you love wood patterns, so here’s one more.
Source Richard Tabor
Fake or not, it’s quite luxurious.
Source Factorio.us Collective
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
A light gray fabric pattern with faded vertical stripes.
Source V. Hartikainen
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Pixel by pixel, sharp and clean. Very light pattern with clear lines.
Source M.Ashok
I guess this one is inspired by an office. A dark office.
Source Andrés Rigo.
I know there is one here already, but this is sexy!
Source Gjermund Gustavsen
Remixed from a drawing in 'Line and form", Walter Crane, 1914.
Source Firkin
Prismatic Curved Diamond Pattern 7 No Background
Source GDJ
Light and tiny, just the way you like it.
Source Rohit Arun Rao