3px Tile #342
 Dark  CC BY-SA 3.0

Tiny dark square tiles with varied color tones.

Source Gre3g

 More Textures
Stone Wall & Dark #1523
 Stone  CC 0

Incoming catena. Stone & well. CC0 texture.

Source Unknow

Block Well #1698
 Colorful  CC 0

Background Wall, Art Abstract, Block Well & CC0 texture.

Source Ractapopulous

Black And White Floral Pattern Background Inverse #197
 Dark  CC 0

Black And White Floral Pattern Background from PDP.

Source GDJ

Background pattern 329 #1769
 Dark  CC 0

A pattern formed entirely from squares

Source Firkin

Red #1247
 Red  CC 0

Zerro CC tillable texture of stones photographed and made by me. CC0

Source Sojan Janso

Prismatic Geometric Tessellation Pattern 2 No [email protected] #554
 Noise  CC 0

Prismatic Geometric Tessellation Pattern 2 No Background

Source GDJ

Grid #974
 Gray  CC BY-SA 3.0

There are quite a few grid patterns, but this one is a super tiny grid with some dust for good measure.

Source Dominik Kiss

Stone Wall & Yellow #1489
 Stone  CC 0

Incoming catena. Stone & well. CC0 texture.

Source Unknow

Lined Paper #1034
 Light  CC BY-SA 3.0

I know there is one here already, but this is sexy!

Source Gjermund Gustavsen

Black Twill #929
 Dark  CC BY-SA 3.0

Trippy little gradients at an angle.

Source Cary Fleming.

"Beige Stone", Tileable Texture #1025
 Stone  CC BY-SA 3.0

"Beige Stone", Tileable Texture.

Source V. Hartikainen

White Bed Sheet #821
 Light  CC BY-SA 3.0

Nothing like a clean set of bed sheets, huh?

Source Badhon Ebrahim

Background pattern brown #1951
 Brown  CC 0

To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Background pattern 308 (colour 3) #1870
 Colorful  CC 0

Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.

Source Firkin

Mix & Black Pattern #1633
 Metal  CC 0

Metal-Plain or Painted. CC0 License.

Source Unknow

Rough Diagonal #691
 Fabric  CC BY-SA 3.0

The classic 45-degree diagonal line pattern, done right.

Source Jorick van Hees

Clean gray [email protected] #860
 Paper  CC BY-SA 3.0

On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.

Source Paul Phönixweiß

Diamond pattern 2 (colour 5) #2264
 Blue  CC 0

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

Source Firkin

Little [email protected] #74
 Light  CC BY-SA 3.0

Subtle grunge and many little pluses on top.

Source Atle Mo

Decorative divider 223 #2207
 Dark  CC 0

Inspired by a design found in 'Konstantinápolyi emlékeim', Miklos Chriszto, 1893.

Source Firkin

Background pattern 314 #1839
 Yellow  CC 0

The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin

Grey Sandbag #641
 Paper  CC BY-SA 3.0

A bit strange this one, but nice at the same time.

Source Diogo Silva

[email protected] #658
 Paper  CC BY-SA 3.0

Nicely crafted paper pattern, although a bit on the large side (500x593px).

Source Blaq Annabiosis

Wavy background #2012
 Green  CC 0

A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic

Source Firkin

Boiler Plate Rust #1644
 Metal  CC 0

Metal-Processed. CC0 License.

Source Unknow

Tree Bark #1182
 Light  CC BY-SA 3.0

This one is something special. I’d call it a flat pattern, too. Very well done, sir!

Source GetDiscount

Retro Circles Background [email protected] #429
 Noise  CC 0

Retro Circles Background 6

Source GDJ