All good things come in threes, so I give you the third in my little concrete wall series.
Source Atle Mo
Like the name suggests, this background image consists of a pattern of dark bricks. It may be an option for you, if you are looking for something that looks like a brick wall for use as a background on web pages. It's not a masterpiece, but looks pretty nice when is tiled.
Source V. Hartikainen
A very slick dark rubber grip pattern, sort of like the grip on a camera.
Source Sinisha
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
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 seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
A smooth mid-tone gray, or low contrast if you will, linen pattern.
Source Jordan Pittman
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A seamless pattern of dark bricks. Maybe it's not very realistic, but it looks good in my opinion.
Source V. Hartikainen
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
A seamless pattern with wide vertical stripes colored in pale yellow.
Source V. Hartikainen
Could remind you a bit of those squares in Super Mario Bros, yeh?
Source Jeff Wall
From a drawing in 'Real Sailor-Songs', John Ashton, 1891.
Source Firkin
Prismatic Groovy Concentric Background No Black
Source GDJ
Dark, square, clean and tidy. What more can you ask for?
Source Jaromír Kavan
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Basic Pattern 2 No Background
Source GDJ
A bit of scratched up grayness. Always good.
Source Dmitry
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857
Source Firkin
Prismatic Curved Diamond Pattern 7 No Background
Source GDJ
A seamless pattern formed from a tile made from ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Geometric Pattern Variation 2 With Background
Source GDJ
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin