Mirrored Squares #123
 Dark  CC BY-SA 3.0

Did some testing with Repper Pro tonight, and this gray mid-tone pattern came out.

Source Atle Mo

 More Textures
Seamless Core Pattern 5 #169
 Dark  CC 0

Seamless Core Pattern 5

Source GDJ

Prismatic Curved Diamond Pattern 8 No Background #549
 Dark  CC 0

Prismatic Curved Diamond Pattern 8 No Background

Source GDJ

Colourful background #2009
 Colorful  CC 0

Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic

Source Firkin

Decorative divider 228 #2154
 Dark  CC 0

Remixed from a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.

Source Firkin

Background pattern 336 (colour 3) #1719
 Blue  CC 0

Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.

Source Firkin

Pattern cleanup filtered 2 #152
 Noise  CC 0

Cleanup with gradients and filtering.

Source Lazur URH

MBossed@2X #194
 Grid  CC BY-SA 3.0

Embossed lines and squares with subtle highlights.

Source Alex Parker

Green Dust & Scratches@2X #108
 Wall  CC BY-SA 3.0

Snap! It’s a pattern, and it’s not grayscale! Of course you can always change the color in Photoshop.

Source Atle Mo

Background pattern 248 #2181
 Dark  CC 0

To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Zodiac sign symbol background #1927
 Red  CC 0

Just the symbols of the signs of the zodiac distributed in a chequer board-like pattern

Source Firkin

Polonez Pattern@2X #335
 Gray  CC BY-SA 3.0

A car pattern?! Can it be subtle? I say yes!

Source Radosław Rzepecki

Decorative divider 230 #2150
 Dark  CC 0

From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.

Source Firkin

Recharging the void #164
 Noise  CC 0

Original effect recreated by a simple filter.

Source Lazur URH