Diamond pattern 2 (colour 3) #2266
 Colorful  CC 0

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

Source Firkin

 More Textures
Background pattern 214 (colour 5) #2374
 Green  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. Alternative colour scheme.

Source Firkin

Prismatic Groovy Concentric Background 3 No Black@2X #460
 Noise  CC 0

Prismatic Groovy Concentric Background 3 No Black

Source GDJ

Prismatic Pointers Background #388
 Noise  CC 0

Prismatic Pointers Background

Source GDJ

Background pattern 238 (colour 3) #2227
 Blue  CC 0

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

Source Firkin

Beige Paper@2X #84
 Paper  CC BY-SA 3.0

This was submitted in a beige color, hence the name. Now it’s a gray paper pattern.

Source Konstantin Ivanov

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

Green Fibers #91
 Dark  CC BY-SA 3.0

The green fibers pattern will work very well in grayscale as well.

Source Matteo Di Capua

Brushed Alum@2X #68
 Light  CC BY-SA 3.0

A light brushed aluminum pattern for your pleasure.

Source Tim Ward