More Textures
Seamless tile 4 #1812
 Red  CC 0

Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern

Source Firkin

Prismatic Groovy Concentric Background 4 No Black@2X #464
 Noise  CC 0

Prismatic Groovy Concentric Background 4 No Black

Source GDJ

Prismatic Curved Diamond Pattern 4 No Background@2X #542
 Diamond  CC 0

Prismatic Curved Diamond Pattern 4 No Background

Source GDJ

Background pattern 112 #263
 Fabric  CC 0

A seamless pattern with a unit cell drawn as a bitmap in Paint.net and vectorized in Vector Magic.

Source Firkin

Background pattern 333 #1741
 Noise  CC 0

The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i

Source Firkin

My Little Plaid #332
 Light  CC BY-SA 3.0

Repeating squares overlapping.

Source Pete Fecteau

Small Crosses #115
 Stripes  CC BY-SA 3.0

Sharp pixel pattern looking like some sort of fabric.

Source Dmitry

Seamless Prismatic Geometric Pattern With Background #264
 Dark  CC 0

Seamless Prismatic Geometric Pattern With Background

Source GDJ

Background pattern 203 (colour 2) #2485
 Green  CC 0

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

Source Firkin

Seamless 3D Isometric Tessellation Pattern 2 #147
 Light  CC 0

A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).

Source GDJ

Colourful bricks pattern (no background) #265
 Noise  CC 0

Original minus the background

Source Firkin

Dark Steel Grid Background Pattern #1081
 Metal  CC BY-SA 3.0

Here's a dark background pattern that contains a steel grid pattern as a texture. Use it as a website background or for other purposes. It's free!

Source V. Hartikainen

Decorative divider 188 #2521
 Dark  CC 0

From a drawing in 'Uit de geschiedenis der Heilige Stede te Amsterdam', Yohannes Sterck, 1898.

Source Firkin

Random Binary Background #274
 Light  CC 0

Random Binary Background

Source GDJ

Candyhole@2X #357
 Light  CC BY-SA 3.0

It’s a hole, in a pattern. On your website. Dig it!

Source Josh Green