A yellow tiled background... Blurriness, bokeh effect and rectangles pattern in one mix.
Source V. Hartikainen
A dark metal plate with an embossed grid pattern and a bit of rust. Here's a dark metal plate texture for use as a tiled background on web pages.
Source V. Hartikainen
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim
A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
A seamless pattern of "sewn stripes" colored in light gray.
Source V. Hartikainen
Subtle scratches on a light gray background.
Source Andrey Ovcharov
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
From a drawing in 'Codogno e il suo territorio nella cronaca e nella storia'', Gio and Giarella Cairo, 1897.
Source Firkin
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Derived from a drawing in 'The Murmur of the Shells', Samuel Cowen, 1879.
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
Background Wall, Art Abstract, Watercolor Vintage style CC0 texture.
Source Ractapopulous
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
From a drawing in 'Uit de geschiedenis der Heilige Stede te Amsterdam', Yohannes Sterck, 1898.
Source Firkin
Prismatic Floral Background No Black
Source GDJ
Prismatic Abstract Line Art Pattern Background 2
Source GDJ
A large (588x375px) sand-colored pattern for your ever-growing collection. Shrink at will.
Source Alex Tapein
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen