Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.
Source Lazur URH
As simple and subtle as it gets. But sometimes that’s just what you want.
Source Designova
Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
It’s a hole, in a pattern. On your website. Dig it!
Source Josh Green
A new one called white wall, not by me this time.
Source Yuji Honzawa
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Seamless Prismatic Quadrilateral Line Art Pattern No Background
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
CC0 remixed from a drawing. Walter Crane, 1914, Firkin.
Source SliverKnight
Prismatic Polka Dots Mark II No Background
Source GDJ
A free background pattern with abstract green tiles.
Source V. Hartikainen
The Grid. A digital frontier. I tried to picture clusters of information as they traveled through the computer.
Source Haris Šumić
A textured orange background pattern with vertical stripes.
Source V. Hartikainen
A seamless pattern based on a tile that can be achieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A huge one at 800x600px. Made from a photo I took going home after work.
Source Atle Mo