Fabric pattern 2 (colour 6) #2391
 Fabric  CC 0

Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

 More Textures
Psychedelic Geometric Background #381
 Noise  CC 0

Psychedelic Geometric Background.

Source GDJ

Real Carbon Fiber@2X #287
 Carbon  CC BY-SA 3.0

Carbon fiber is never out of fashion, so here is one more style for you.

Source Alfred Lee

Background pattern 266 #2068
 Dark  CC 0

Remixed from a drawing in 'Some account of the Worshipful Company of Ironmongers', John Nicholl, 1866.

Source Firkin

Black Mamba@2X #58
 Dark  CC BY-SA 3.0

The name alone is awesome, but so is this sweet dark pattern.

Source Federica Pelzel

Project Papper #119
 Paper  CC BY-SA 3.0

Light square grid pattern, great for a “DIY projects” sort of website, maybe?

Source Rafael Almeida

Prismatic Dots Background 7@2X #514
 Dark  CC 0

Prismatic Dots Background 7

Source GDJ

Paper 2@2X #22
 Paper  CC BY-SA 3.0

New paper pattern with a slightly organic feel to it, using some thin threads.

Source Atle Mo

Prismatic Abstract Geometric Background 2 No Black #445
 Noise  CC 0

Prismatic Abstract Geometric Background 2 No Black

Source GDJ

Background pattern 339 (colour 2) #1707
 Green  CC 0

The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin