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 pale orange background pattern with glossy groove stripes.
Source V. Hartikainen
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Looks like an old rug or a computer chip.
Source Patutin Sergey
Zero CC tileable hard cover cells book texture, 4k, scanned and made by me. CC0
Source Sojan Janso
A comeback for you: the popular Escheresque, now in black.
Source Patten
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
One of the few full-color patterns here, but this one was just too good to pass up.
Source Alexey Usoltsev
An emulated “transparent” background pattern, like that of all kinds of computer graphics software.
Source AdamStanislav
Here is a new seamless wood texture for using as blog or website backgrounds.
Source V. Hartikainen
Adapted from an image that was uploaded to Pixabay by Anerma.
Source Firkin
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Remixed from a drawing in 'A Girl in Ten Thousand', Elizabeth Meade, 1896.
Source Firkin
Floral patterns will never go out of style, so enjoy this one.
Source Lasma
Derived from an image that was uploaded to Pixabay by Darkmoon1968
Source Firkin
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
A very dark asfalt pattern based off of a photo taken with my iPhone.
Source Atle Mo
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Formed by heavily distorting part of a an image of a fish uploaded to Pixabay by GLady
Source Firkin