A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Here's a subtle marble-like background for use on websites.
Source V. Hartikainen
A free seamless background texture that looks like a brown stone wall.
Source V. Hartikainen
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
A seamless pattern made from the gold Penrose triangle by GDJ and the two remixes
Source Firkin
This is lovely, just the right amount of subtle noise, lines and textures.
Source Richard Tabor
The image depicts a seamless pattern of a snow crystal.I referred to a book called ”sekka-zusetsu” or "雪華図説" which means an illustrated explanation about snow crystals.This book was published in 1832 (天保3年) or Edo period.For more about "雪華図説",see here:dl.ndl.go.jp/info:ndljp/pid/2536975
Source Yamachem
By popular request, an outline version of the pentagon pattern.
Source Atle Mo
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
Seamless pattern made from a tile that can be obtained in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.
Source Firkin
A rusty grunge background for websites. Feel free to use it in your site's theme.
Source V. Hartikainen
A repeating background with seamless texture of stone. There haven't been any stone-like backgrounds for a while, so I have decided to create one more. The rest can be found in the appropriate category.
Source V. Hartikainen
An abstract texture of black metal pipes (seamless).
Source V. Hartikainen
Black And White Floral Pattern Background from PDP.
Source GDJ