Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Tiny little flowers growing on your screen. Nice, huh?
Source Themes Tube
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
This seamless background image should look nice on websites. It has a dark blue gray texture with vertical stripes, it tiles seamlessly and, like all of the background images here, it's free. So, if you like it, take it!
Source V. Hartikainen
A light gray background pattern with seamless fabric-like texture and almost unnoticeable stripes.
Source V. Hartikainen
Remixed from a drawing that was uploaded to Pixabay by captenpub.
Source Firkin
Derived from an image that was uploaded to Pixabay by mdmelo.
Source Firkin
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
A nice and simple white rotated tile pattern.
Source Another One
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
There are many carbon patterns, but this one is tiny.
Source Designova
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
A slightly grainy paper pattern with small horizontal and vertical strokes.
Source Atle Mo
No relation to the band, but damn it’s subtle!
Source Thomas Myrman