A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.
Source V. Hartikainen
Same as Silver Scales, but in black. Turn your site into a dragon with this great scale pattern.
Source Alex Parker
Not sure if this is related to the Nami you get in Google image search, but hey, it’s nice!
Source Dertig Media
Inspired by a pattern found in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A repeatable image with dark background and metal grid pattern.
Source V. Hartikainen
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
Original minus the background
Source Firkin
Geometric triangles seem to be quite hot these days.
Source Pixeden
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Colorful Floral Background 3 No Black
Source GDJ
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
From a drawing in 'Handbook of the excursions proposed to be made by the Lincoln Diocesan Architectural Society, on the 27th and 28th of May, 1857', Edward Trollope, 1857.
Source Firkin
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
A very dark asfalt pattern based off of a photo taken with my iPhone.
Source Atle Mo
Remixed from a drawing in 'Hungary. A guide book. By several authors', 1890.
Source Firkin
Light honeycomb pattern made up of the classic hexagon shape.
Source Federica Pelzel
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
After 1 comes 2, same but different. You get the idea.
Source Hendrik Lammers
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin