Background Patterns - Bronze #246
 Fabric  CC 0

If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117

Source Viscious-Speed

 More Textures
Green Fibers #91
 Dark  CC BY-SA 3.0

The green fibers pattern will work very well in grayscale as well.

Source Matteo Di Capua

Prismatic Groovy Concentric Background 3 No Black #459
 Noise  CC 0

Prismatic Groovy Concentric Background 3 No Black

Source GDJ

Background pattern 15 #201
 Dark  CC 0

A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.

Source Firkin

Prismatic Groovy Concentric Background 5@2X #466
 Dark  CC 0

Prismatic Groovy Concentric Background 5

Source GDJ

Padded@2X #62
 Dark  CC BY-SA 3.0

A beautiful dark padded pattern, like an old classic sofa.

Source Chris Baldie

Prismatic Triangular Background Design Mark II 5 #406
 Dark  CC 0

Prismatic Triangular Background Design Mark II 5

Source GDJ

Element of beach pattern with background #254
 Noise  CC 0

Element of beach pattern with background.

Source Rones