Diamond Eyes #685
 Diamond  CC BY-SA 3.0

Everyone loves a diamond, right? Make your site sparkle.

Source AJ Troxell

 More Textures
Rustymetal Glossy #1647
 Metal  CC 0

Metal-Rusty. CC0 License.

Source Unknow

Grid Me #605
 Grid  CC BY-SA 3.0

Nice little grid. Would work great as a base on top of some other patterns.

Source Arno Gregorian

Background pattern 214 #2377
 Blue  CC 0

A seamless chequerboard pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.

Source Firkin

Seamless Blue On Yellow Background #1160
 Grid  CC BY-SA 3.0

This seamless pattern consists of a blue grid on a yellow background.

Source V. Hartikainen

Floral pattern 3 (colour) #2330
 Colorful  CC 0

Adapted from a jpg on Pixabay.

Source Firkin

Leaded glass background (colour 5) #2050
 Colorful  CC 0

Seamless pattern the tile.

Source Firkin

Abstract Water Texture (Seamless) #890
 Water  CC BY-SA 3.0

An abstract texture of water. It's not perfect, but will do. You may download if you like it.

Source V. Hartikainen

Leaves #1669
 Paper  CC 0

Paper-Wallpaper. CC0 License.

Source Unknow

Silver [email protected] #190
 Light  CC BY-SA 3.0

Turn your site into a dragon with this great scale pattern.

Source Alex Parker

Retro Squares Background 9 #399
 Dark  CC 0

Retro Squares Background 9

Source GDJ

Prismatic Abstract Geometric Background 4 No [email protected]@2X #444
 Dark  CC 0

Prismatic Abstract Geometric Background 4

Source GDJ

Subtle Grunge #1040
 Light  CC BY-SA 3.0

A heavy hitter at 400x400px, but lovely still.

Source Breezi

Stone Wall & Red #1505
 Red  CC 0

Incoming catena. Stone & well. CC0 texture.

Source Unknow

Whitey #109
 Light  CC BY-SA 3.0

A white version of the very popular linen pattern.

Source Ant Ekşiler

Vintage Clay Tile 6 #1463
 Unknow  CC 0

Gamedev - Roofs Textures. CC0 License.

Source Davit Masia

Dungeons & Flagons 8 #1424
 Diamond  CC 0

Gamedev - Floors Textures. CC0 License.

Source Davit Masia

Background pattern 329 #1769
 Dark  CC 0

A pattern formed entirely from squares

Source Firkin

Grass #1278
 Green  CC 0

Zero CC tileable grass texture, photographed and made by me. CC0

Source Sojan Janso

Decorative divider 250 #2070
 Dark  CC 0

Remixed from a drawing in 'Очерки Русской Исторіи въ памятникахъ быта', Petr Polevoi, 1879.

Source Firkin

Prismatic Abstract Geometric Background 2 No [email protected] #446
 Noise  CC 0

Prismatic Abstract Geometric Background 2 No Black

Source GDJ

cloth texture #2454
 Fabric  CC 0

This is a light-brown cloth texture.

Source Yamachem

Background pattern 221 (colour) #2346
 Yellow  CC 0

A seamless pattern formed from a tile made from page ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Shattered #951
 Gray  CC BY-SA 3.0

A large pattern with funky shapes and form. An original. Sort of origami-ish.

Source Luuk van Baars

Background pattern 223 #2353
 Red  CC 0

Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

overlay crack #153
 Noise  CC 0

This pack of filters can help you adding a blocky overlay to objects. May come handy at drawing blocks of stone.

Source Lazur URH

Redox 02 #851
 Light  CC BY-SA 3.0

After 1 comes 2, same but different. You get the idea.

Source Hendrik Lammers

Cubes #133
 Light  CC BY-SA 3.0

This reminds me of Game Cube. A nice light 3D cube pattern.

Source Sander Ottens

Stacked [email protected] #674
 Light  CC BY-SA 3.0

A simple circle. That’s all it takes. This one is even transparent, for those who like that.

Source Saqib

Seamless Gray Stone Background #1028
 Stone  CC BY-SA 3.0

This background image has seamless texture that resembles a surface of gray stone.

Source V. Hartikainen