Scanned some rice paper and tiled it up for you. Enjoy.
Source Atle Mo
You may use it as is, or modify it as you like.
Source V. Hartikainen
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
A free black metallic background pattern. Here's a new pattern I made that looks metallic.
Source V. Hartikainen
Floral patterns will never go out of style, so enjoy this one.
Source Lasma
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Prismatic Geometric Pattern Background 2 No Black
Source GDJ
An abstract Background pattern of purple twisty patterns.
Source TikiGiki
From a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Just like your old suit, all striped and smooth.
Source Alex Berkowitz
A pattern derived from repeating unit cells each derived from part of a mosaic in paint.net. The starting point for the mosaic was a picture of some prawns!
Source Firkin
Prismatic Isometric Cube Wireframe Pattern No Background
Source GDJ
Here's a tile-able wood background image for use in web design.
Source V. Hartikainen
Prismatic Abstract Geometric Background 4
Source GDJ