Soft Kill@2X #319
 Dark  CC BY-SA 3.0

Pattern #100! A black classic knit-looking pattern.

Source Factorio.us Collective

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

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

Source Radosław Rzepecki

Psychedelic Geometric Background No Black #382
 Noise  CC 0

Psychedelic Geometric Background No Black

Source GDJ

Background pattern 314 (colour 2) #1838
 Green  CC 0

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

Source Firkin

Gold Scale@2X #285
 Light  CC BY-SA 3.0

More Japanese-inspired patterns, Gold Scales this time.

Source Josh Green

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

"Polished Stone", Gray Background Pattern #1053
 Stone  CC BY-SA 3.0

A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).

Source V. Hartikainen

Prismatic Abstract Geometric Background 4 No Black@2X #442
 Dark  CC 0

Prismatic Abstract Geometric Background 4 No Black

Source GDJ

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

Colorful Floral Background 2

Source GDJ

White Plaster@2X #369
 Wall  CC BY-SA 3.0

Sweet and subtle white plaster with hints of noise and grunge.

Source Phil Maurer

Dark Circles #306
 Dark  CC BY-SA 3.0

People seem to enjoy dark patterns, so here is one with some circles.

Source Atle Mo

Triangles pattern #2408
 Brown  CC 0

A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin