Carbon Fiber v2@2X #106
 Carbon  CC BY-SA 3.0

One more updated pattern. Not really carbon fiber, but it’s the most popular pattern, so I’ll give you an extra choice.

Source Atle Mo

 More Textures
Background pattern 231 #2301
 Dark  CC 0

A seamless pattern based on a tile that can be achieved by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Decorative divider 232 #2148
 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

Prismatic Snowflakes Pattern 2 No Background #412
 Light  CC 0

Prismatic Snowflakes Pattern 2 No Background

Source GDJ

Diagonal Noise #181
 Fabric  CC BY-SA 3.0

A simple but elegant classic. Every collection needs one of these.

Source Christopher Burton

Type #276
 Dark  CC BY-SA 3.0

The perfect pattern for all your blogs about type, or type-related matters.

Source Atle Mo

Green Gobbler #85
 Dark  CC BY-SA 3.0

Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.

Source Simon Meek

Prismatic Groovy Concentric Background 4 No Black@2X #464
 Noise  CC 0

Prismatic Groovy Concentric Background 4 No Black

Source GDJ

Diagonal Noise@2X #182
 Fabric  CC BY-SA 3.0

A simple but elegant classic. Every collection needs one of these.

Source Christopher Burton

Seamless Core Pattern 10 #171
 Dark  CC 0

Seamless Core Pattern 10

Source GDJ

Background pattern green #1944
 Green  CC 0

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

Source Firkin