From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
Mostly just mucked about with the colours and made one of the paths in the lead frame opaque. The glass remains transparent.
Source Firkin
Prismatic Groovy Concentric Background 3
Source GDJ
Simple combination of stripy squares with their negatively coloured counterparts
Source Firkin
Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
A seamless pattern formed from background pattern 102
Source Firkin
The classic notebook paper with horizontal stripes.
Source Are Sundnes
A car pattern?! Can it be subtle? I say yes!
Source Radosław Rzepecki
Might not be super subtle, but quite original in its form.
Source Alex Smith
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
Here's a subtle marble-like background for use on websites.
Source V. Hartikainen
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A seamless pattern formed from cross 4. To get the original tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
Kaleidoscope Prismatic Abstract No Background
Source GDJ
Your eyes can trip a bit from looking at this – use it wisely.
Source Michal Chovanec
No idea what Nistri means, but it’s a crisp little pattern nonetheless.
Source Markus Reiter
Abstract Stars Geometric Pattern Prismatic No Background
Source GDJ
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
The classic subtle pattern. Sort of wall/brick looking. Or moon-looking?
Source Joel Klein