To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This is a hot one. Small, sharp and unique.
Source GraphicsWall
Inspired by this, I came up with this pattern. Madness!
Source Atle Mo
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
The starting point for this was drawn on the web site steamcoded.org/PolyskelionMaker.svg
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A mid-tone gray pattern with some cement looking texture.
Source Hendrik Lammers
Prismatic Abstract Geometric Background 5
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A blue background wallpaper for websites. It has a seamless texture with vertical stripes. It looks quite nice not only when using as a tiled background on websites, but also on computer desktops.
Source V. Hartikainen
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
Remixed from a drawing in 'Works. Popular edition', John Ruskin, 1886.
Source Firkin
One more from Badhon, sharp horizontal lines making an embossed paper feeling.
Source Badhon Ebrahim
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin