Dark Circles@2X #307
 Dark  CC BY-SA 3.0

People seem to enjoy dark patterns, so here is one with some circles.

Source Atle Mo

 More Textures
Prismatic Polka Dots Mark II No Background@2X #531
 Noise  CC 0

Prismatic Polka Dots Mark II No Background

Source GDJ

Retro Circles Background 7 #431
 Unknow  CC 0

Retro Circles Background 7

Source GDJ

Diamond pattern (colour 9) #2269
 Fabric  CC 0

From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Prismatic Abstract Geometric Background 5 #401
 Noise  CC 0

Prismatic Abstract Geometric Background 5

Source GDJ

pattern cleanup filtered #151
 Noise  CC 0

With a fabric filter added.Tags

Source Lazur URH

Pattern generator #161
 Noise  CC 0

A simple example on using clones. You can generate a nice base for a pattern fill quickly with it.

Source Lazur URH

Little Knobs #310
 Light  CC BY-SA 3.0

White little knobs, coming in at 10x10px. Sweet!

Source Amos

Prismatic Dots Background 6@2X #512
 Dark  CC 0

Prismatic Dots Background 6

Source GDJ

Background pattern 8 (greyscale) #210
 Dark  CC 0

Greyscale version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net

Source Firkin

Carbon Fiber Big #326
 Carbon  CC BY-SA 3.0

Bigger is better, right? So here you have some large carbon fiber.

Source Factorio.us Collective

Tessellation 9 #2548
 Grid  CC 0

A seamless tessellation pattern. To get the tile this is formed from, select the pattern in Inkscape and use shift+alt+i.

Source Firkin

Vintage pattern #1961
 Grid  CC 0

Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.

Source Firkin

"Maple", Seamless Wood Texture #883
 Wood  CC BY-SA 3.0

Here I have tried to create something that would look like maple wood. Not sure how well it's turned out, but at least it looks like wood.

Source V. Hartikainen

Decorative divider 231 #2149
 Dark  CC 0

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