Broken Noise #364
 Dark  CC BY-SA 3.0

Beautiful dark noise pattern with some dust and grunge.

Source Vincent Klaiber

 More Textures
Background pattern 19 (outline) #204
 Light  CC 0

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

Source Firkin

Geometric pattern #2004
 Grid  CC 0

A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i

Source Firkin

Greek key pattern 5 #2294
 Dark  CC 0

Seamless pattern made from a tile that can be obtained in Inkscape by selecting the rectangle and using shift+alt+i.

Source Firkin

Brushed Alum Dark@2X #66
 Dark  CC BY-SA 3.0

Because I love dark patterns, here is Brushed Alum in a dark coating.

Source Tim Ward

Colorful Stripes Background #400
 Noise  CC 0

Colorful Stripes Background

Source GDJ