This one is amazing, truly original. Go use it!
Source Viahorizon
Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic
Source Firkin
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern
Source Firkin
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
Prismatic Geometric Pattern Background No Black
Source GDJ
Zero CC Mossy stone tileable texture, photographed and made by me. CC0
Source Sojan Janso
Beautiful dark noise pattern with some dust and grunge.
Source Vincent Klaiber
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A new one called white wall, not by me this time.
Source Yuji Honzawa
Number five from the same submitter, makes my job easy.
Source Dima Shiper
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
White fabric looking texture with some nice random wave features.
Source Hendrik Lammers
Alternative colour scheme for the original floral pattern.
Source Firkin
A brown metallic grid pattern layered on top of a dark fabric texture. It should look great when using as a tiled background on web pages, especially blogs.
Source V. Hartikainen
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamlessly tileable pink background texture.
Source V. Hartikainen
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin