Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Nicely executed tiling for an interesting pattern.
Source Ignasi Àvila Padró
Prismatic Groovy Concentric Background
Source GDJ
The image a seamless pattern derived from a weed which I can't identify.The original weed image is from here:https://jp.pinterest.com/pin/500744052301423641/
Source Yamachem
A slightly more textured pattern, medium gray. A bit like a potato sack?
Source Bilal Ketab
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Brushed aluminum, in a bright gray version. Lovely 2X as well.
Source Andre Schouten
Lovely pattern with some good-looking non-random noise lines.
Source Zucx
Remixed from a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
Remixed from a drawing in 'An Index to Deering's Nottinghamia Vetus et Nova', Rupert Chicken, 1899. The unit tile can be had by selecting the rectangle in Inkscape and using shift-alt-i
Source Firkin
A seamless pattern formed from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Prismatic Hexagonalist Pattern No Background
Source GDJ
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
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
Remixed from a PNG that was uploaded to Pixabay by gingertea
Source Firkin
Inspired by a drawing in 'Kulturgeschichte', Freidrich Hellwald, 1896.
Source Firkin
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
The original has been presented as black on transparent and stored in the pattern definitions. To retrieve the unit tile select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Did anyone say The Hoff? This pattern is in no way related to Baywatch.
Source Josh Green
Formed by distorting a JPG from PublicDomainPictures
Source Firkin
From a drawing in 'Studies for Stories', Jean Ingelow, 1864.
Source Firkin
It’s okay to be square! A nice light gray pattern with random squares.
Source Waseem Dahman
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida