As far as fabric patterns goes, this is quite crisp.
Source Heliodor Jalba
Zero CC tileable pine bark texture, photographed and made by me. CC0
Source Sojan Janso
Same as the black version, but now in shades of gray. Very subtle and fine grained.
Source Atle Mo
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
A hint of orange color, and some crossed and embossed lines.
Source Adam Anlauf
Dare I call this a «flat pattern»? Probably not.
Source Dax Kieran
Green Background Pattern
Source V. Hartikainen
To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Remixed from a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
A seamless green background texture. The image is distributed under a Creative Commons License (like all of the images here).
Source V. Hartikainen
Background pattern originally a PNG drawn in Paint.net
Source Firkin
A seamless dark leather-like background texture with diagonal lines that look like stitches.
Source V. Hartikainen
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Nicely crafted paper pattern, although a bit on the large side (500x593px).
Source Blaq Annabiosis
I asked Gjermund if he could make a pattern for us – result!
Source Gjermund Gustavsen
Nothing like a clean set of bed sheets, huh?
Source Badhon Ebrahim
Old China with a modern twist, take two.
Source Adam Charlts
Sometimes you just need the simplest thing.
Source Fabricio
This background pattern contains a texture of yellow wood planks. I think it looks quite original.
Source V. Hartikainen
Prismatic Groovy Concentric Background 2 No Black
Source GDJ
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed