Dark Brick Wall@2X #136
 Wall  CC BY-SA 3.0

Black brick wall pattern. Brick your site up!

Source Alex Parker

 More Textures
Retina Dust #915
 Light  CC BY-SA 3.0

First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.

Source Atle Mo

Vichy #71
 Light  CC BY-SA 3.0

This one could be the shirt of a golf player. Angled lines in different thicknesses.

Source Olivier Pineda

Electric recharge #163
 Noise  CC 0

Simple turbulence filter rigged in in inkscape.

Source Lazur URH

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

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

Source Struck Axiom

Medic Packaging Foil@2X #377
 Light  CC BY-SA 3.0

8 by 8 pixels, and just what the title says.

Source pixilated

Colourful background #2007
 Colorful  CC 0

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

Source Firkin

Starring@2X #586
 Dark  CC BY-SA 3.0

If you need stars, this is the one to get.

Source Agus Riyadi

Colorful Floral Background 2@2X #488
 Dark  CC 0

Colorful Floral Background 2

Source GDJ

Floral Pattern Background 3 #218
 Noise  CC 0

PDP

Source GDJ

Silver Scales #189
 Light  CC BY-SA 3.0

Turn your site into a dragon with this great scale pattern.

Source Alex Parker