Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
Detailed but still subtle and quite original. Lovely gray shades.
Source Kim Ruddock
A seamless pale yellow paper background with a pattern of animal tracks.
Source V. Hartikainen
A comeback for you: the popular Escheresque, now in black.
Source Patten
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A beautiful dark padded pattern, like an old classic sofa.
Source Chris Baldie
Zero CC tileable Laminate wood texture, photographed and made by me. CC0
Source Sojan Janso
A background pattern with green vertical stripes. A new striped background pattern. This time a green one.
Source V. Hartikainen
Prismatic Polka Dots 3 No Background
Source GDJ
Paper pattern with small dust particles and 45-degree strokes.
Source Atle Mo
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
I’m not going to lie – if you submit something with the words Norwegian and Rose in it, it’s likely I’ll publish it.
Source Fredrik Scheide
Abstract Tiled Background Extended 11
Source GDJ
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Just what the name says, paper fibers. Always good to have.
Source Heliodor jalba
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Here's a brown background pattern with subtle stripes. I hope you'll like the color. If not, feel free to change it using an image editor, if you know how of course. Personally, I'm using GIMP to create these backgrounds.
Source V. Hartikainen
This background pattern contains a seamless texture of bark. It's not very realistic, but I think it looks quite nice.
Source V. Hartikainen
Prismatic 3D Isometric Tessellation Pattern 6
Source GDJ
Prismatic Geometric Pattern Background 2
Source GDJ
A comeback for you: the popular Escheresque, now in black.
Source Patten
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using 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