Background pattern 223 (colour 2) #2352
 Blue  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

 More Textures
Broken Noise #364
 Dark  CC BY-SA 3.0

Beautiful dark noise pattern with some dust and grunge.

Source Vincent Klaiber

White carbon #11
 Carbon  CC BY-SA 3.0

Same as the black version, but now in shades of gray. Very subtle and fine grained.

Source Atle Mo

Background pattern 252 (colour 5) #2158
 Light  CC 0

Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Circles #185
 Light  CC BY-SA 3.0

One more sharp little tile for you. Subtle circles this time.

Source Blunia

Seamless Colorful Floral Pattern Background #256
 Fabric  CC 0

PDP

Source GDJ

Polaroid #187
 Wall  CC BY-SA 3.0

Smooth Polaroid pattern with a light blue tint.

Source Daniel Beaton

Rice Paper@2X #339
 Paper  CC BY-SA 3.0

Scanned some rice paper and tiled it up for you. Enjoy.

Source Atle Mo

Connected #348
 Light  CC BY-SA 3.0

White circles connecting on a light gray background.

Source Mark Collins

Background pattern pink #1954
 Pink  CC 0

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

Source Firkin

Decorative divider 219 #2231
 Dark  CC 0

Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.

Source Firkin

Background pattern yellow #1999
 Yellow  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

Background pattern black #2026
 Dark  CC 0

Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Batthern #324
 Grid  CC BY-SA 3.0

Sometimes simple really is what you need, and this could fit you well.

Source Factorio.us Collective

Retro Squares Background 2@2X #417
 Noise  CC 0

Retro Squares Background 2

Source GDJ

Axiom Pattern@2X #331
 Grid  CC BY-SA 3.0

Not even 1kb, but very stylish. Gray thin lines.

Source Struck Axiom

Grunge Wall #81
 Wall  CC BY-SA 3.0

Light gray grunge wall with a nice texture overlay.

Source Adam Anlauf