A seamless pattern created from a square tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A cute x, if you need that sort of thing.
Source Juan Scrocchi
Used in small doses, this could be a nice subtle pattern. Used on a large surface, it’s dirty!
Source Paul Reulat
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
Nasty or not, it’s a nice pattern that tiles. Like they all do.
Source Badhon Ebrahim
A seamless pattern made from the gold Penrose triangle by GDJ and the two remixes
Source Firkin
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Retro Circles Background 4 No Black
Source GDJ
CC0 and seamless wellington boot pattern.
Source SliverKnight
Textured Red Brown Plastic, Free Background Pattern. Although there's already enough plastic in our lives, let's bring it to the web too.)
Source V. Hartikainen
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
This one is so simple, yet so good. And you know it. Has to be in the collection.
Source Gluszczenko
The starting point for this was drawn on the web site steamcoded.org/PolyskelionMaker.svg
Source Firkin
Bigger is better, right? So here you have some large carbon fiber.
Source Factorio.us Collective
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Abstract Stars Geometric Pattern Prismatic No Background
Source GDJ