Not so subtle. These tileable wood patterns are very useful.
Source Elemis
Submitted by DomainsInfo – wtf, right? But hey, a free pattern.
Source DomainsInfo
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
Number 2 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Remixed from a drawing in 'A Child of the Age', Francis Adams, 1894.
Source Firkin
This one could be the shirt of a golf player. Angled lines in different thicknesses.
Source Olivier Pineda
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.
Source Firkin
This one takes you back to math class. Classic mathematic board underlay.
Source Josh Green
This makes me wanna shoot some pool! Sweet green pool table pattern.
Source Caveman
From a drawing in 'Hyde Park from Domesday-Book to date', John Ashton, 1896.
Source Firkin
Prismatic Curved Diamond Pattern 3 No Background
Source GDJ
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
From an image on opengameart.org shared by rubberduck.
Source Firkin
A lovely light gray pattern with stripes and a dash of noise.
Source V. Hartikainen
A bit strange this one, but nice at the same time.
Source Diogo Silva
8 by 8 pixels, and just what the title says.
Source pixilated
Prismatic Abstract Geometric Background 5
Source GDJ
An alternative colour scheme for the original seamless texture formed from an image on Pixabay.
Source Firkin
A seamless background pattern with impressed gray dots.
Source V. Hartikainen
Prismatic Curved Diamond Pattern No Background
Source GDJ