Glass block pattern #2477
 Brown  CC 0

Produced using the clouds, flames and glass blocks plug-ins in Paint.net and the resulting .PNG vectorised with Vector Magic.

Source Firkin

 More Textures
Old Mathematics #43
 Stripes  CC BY-SA 3.0

This one takes you back to math class. Classic mathematic board underlay.

Source Josh Green

Pineapple Cut #583
 Diamond  CC BY-SA 3.0

I love the movie Pineapple Express, and I’m also liking this Pineapple right here.

Source Audee Mirza

Triangular Psychosis 3 #235
 Noise  CC 0

A colorful triangular background, variation 3.

Source GDJ

Background pattern 225 (colour 3) #2325
 Pink  CC 0

Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

Prismatic Geometric Tessellation Pattern 3 No Background #555
 Noise  CC 0

Prismatic Geometric Tessellation Pattern 3 No Background

Source GDJ

Always Grey #53
 Dark  CC BY-SA 3.0

Crossing lines with a subtle emboss effect on a dark background.

Source Stefan Aleksić

Light Aluminum #304
 Wall  CC BY-SA 3.0

Used correctly, this could be nice. Used in a bad way, all hell will break loose.

Source Atle Mo