Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
A free black metallic background pattern. Here's a new pattern I made that looks metallic.
Source V. Hartikainen
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
A colourful background drawn originally in paint.net and vectorised in Vector Magic.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
An abstract web texture of a polished blue stone (or does it look more like ice).
Source V. Hartikainen
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Turn your site into a dragon with this great scale pattern.
Source Alex Parker
If you’re sick of the fancy 3D, grunge and noisy patterns, take a look at this flat 2D brick wall.
Source Listvetra
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
White circles connecting on a light gray background.
Source Mark Collins
Hexagonal dark 3D pattern. What more can you ask for?
Source Norbert Levajsics
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Prismatic Curved Diamond Pattern 5 No Background
Source GDJ
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
A pale yellow background pattern with vertical stripes. The stripes are partially faded. I think this background image turned out pretty well, especially those faded stripes.
Source V. Hartikainen
Free tiled background with colorful stripes and white splatter.
Source V. Hartikainen