Sort of reminds me of those old house wallpapers.
Source Tish
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.
Source Paul Phönixweiß
A pattern derived from repeating unit cells each derived from part of a fractal rendering in paint.net.
Source Firkin
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
Seamless Green Tile Background
Source V. Hartikainen
Prismatic Chevrons Pattern 5 With Background
Source GDJ
Embossed lines and squares with subtle highlights.
Source Alex Parker
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
One more sharp little tile for you. Subtle circles this time.
Source Blunia
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
Prismatic Polka Dots Mark II 3 No Background
Source GDJ
This is lovely, just the right amount of subtle noise, lines and textures.
Source Richard Tabor
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
Prismatic Geometric Pattern Background 2
Source GDJ
With a name this awesome, how can I go wrong?
Source Nikolay Boltachev
You just can’t get enough of the fabric patterns, so here is one more for your collection.
Source Krisp Designs
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
The original enhanced with one of Inkscapes's filters.
Source Firkin