A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
Classic 45-degree pattern, light version.
Source Luke McDonald
Super simple but very nice indeed. Gray with vertical stripes.
Source Merrin Macleod
An interesting dark spotted pattern at an angle.
Source Hendrik Lammers
This is the remix of "Background pattern 115" uploaded by "Firkin".Thanks.
Source Yamachem
Feel free to use this seamless background texture as a background on a web site. It's colored in a light pink color and is seamlessly tile-able.
Source V. Hartikainen
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
A pattern formed from repeated instances of corner decoration 8. To get the basic tile select the rectangle in Inkscape and use shift+alt+i
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
A seamless pattern formed from a rectangular tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
Abstract Ellipses Background Grayscale
Source GDJ
This background pattern contains worn out colorful stripes as a texture.
Source V. Hartikainen
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
A comeback for you: the popular Escheresque, now in black.
Source Patten
A seamless web background with texture of aged grid paper.
Source V. Hartikainen
Prismatic Curved Diamond Pattern 7 No Background
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
This is so subtle you need to bring your magnifier!
Source Carlos Valdez