Seamless pattern made from a tile that can be obtained in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
This ons is quite old school looking. Retro, even. I like it.
Source Arno Declercq
A comeback for you: the popular Escheresque, now in black.
Source Patten
Three shades of gray makes this pattern look like a small carbon fiber surface. Great readability even for small fonts.
Source Atle Mo
Almost like little fish shells, or dragon skin.
Source Graphiste
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Fix and cc0 to get the tile this is based on.
Source SliverKnight
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
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 Polka Dots Mark II 2 No Background
Source GDJ
Zero CC tileable grass texture, photographed and made by me. CC0
Source Sojan Janso
Never out of fashion and so much hotter than the 45º everyone knows, here is a sweet 60º line pattern.
Source Atle Mo
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
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
A bit of scratched up grayness. Always good.
Source Dmitry
A background pattern with a look of rough fabric.
Source V. Hartikainen
Geometric triangles seem to be quite hot these days.
Source Pixeden
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Neat little photography icon pattern.
Source Hossam Elbialy