Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Prismatic Abstract Line Art Pattern Background 2
Source GDJ
Zero CC asphalt, pavement, texture, photographed and made by me. CC0 WARNING I FOUND A SEAM ON THIS TEXTURE
Source Sojan Janso
Here's a tile-able wood background image for use in web design.
Source V. Hartikainen
A seamless pattern the starting point for which was a 'light rays' rendering in Paint.net.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Remixed from a drawing in 'Line and form", Walter Crane, 1914.
Source Firkin
The original enhanced with one of Inkscapes's filters.
Source Firkin
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Prismatic Polka Dots Mark II 3 No Background
Source GDJ
A large pattern with funky shapes and form. An original. Sort of origami-ish.
Source Luuk van Baars
Inspired by a drawing in 'Kulturgeschichte', Freidrich Hellwald, 1896.
Source Firkin
Remixed from a drawing in 'Очерки Русской Исторіи въ памятникахъ быта', Petr Polevoi, 1879.
Source Firkin
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.
Source Firkin
Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
A dark pattern made out of 3×3 circles and a 1px shadow. This works well as a carbon texture or background.
Source Atle Mo