Brushed Alum Dark #65
 Dark  CC BY-SA 3.0

Because I love dark patterns, here is Brushed Alum in a dark coating.

Source Tim Ward

 More Textures
Background pattern 328 (colour 3) #1799
 Noise  CC 0

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

Source Firkin

Soft Circle Scales #113
 Light  CC BY-SA 3.0

Japanese looking fish scale pattern.

Source Ian Soper

Cincinnati tablet 2 #2146
 Dark  CC 0

Remixed from a drawing in 'Prehistoric Man: researches into the origin of civilisation in the old and the new world', Daniel Wilson, 1876.

Source Firkin

Prismatic Dots Background 6 #511
 Dark  CC 0

Prismatic Dots Background 6

Source GDJ

Background pattern 10 #216
 Noise  CC 0

A pattern drawn in Paint.net and vectorized in Vector Magic.

Source Firkin

White Texture #131
 Light  CC BY-SA 3.0

Not the most creative name, but it’s a good all-purpose light background.

Source Dmitry

Squares@2X #303
 Dark  CC BY-SA 3.0

Dark, square, clean and tidy. What more can you ask for?

Source Jaromír Kavan

Colorful Floral Background 3 #483
 Dark  CC 0

Colorful Floral Background 3

Source GDJ