More Textures
Diamonds Are Forever@2X #184
 Diamond  CC BY-SA 3.0

Sharp diamond pattern. A small 24x18px tile.

Source Tom Neal

Green Dust & Scratches #107
 Wall  CC BY-SA 3.0

Snap! It’s a pattern, and it’s not grayscale! Of course you can always change the color in Photoshop.

Source Atle Mo

Prismatic Geometric Pattern Background #407
 Noise  CC 0

Prismatic Geometric Pattern Background

Source GDJ

Seamless tile 4 #1812
 Red  CC 0

Not strictly seamless in that opposite edges are not identical. But they do marry up to make an interesting pattern

Source Firkin

Element of beach pattern with background #254
 Noise  CC 0

Element of beach pattern with background.

Source Rones

Checkered Light Emboss@2X #281
 Grid  CC BY-SA 3.0

Sort of like the Photoshop transparent background, but better!

Source Alex Parker

Prismatic Pointers Background #388
 Noise  CC 0

Prismatic Pointers Background

Source GDJ

Green Fibers@2X #92
 Dark  CC BY-SA 3.0

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

Source Matteo Di Capua

Circles@2X #186
 Light  CC BY-SA 3.0

One more sharp little tile for you. Subtle circles this time.

Source Blunia

Old Mathematics@2X #44
 Stripes  CC BY-SA 3.0

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

Source Josh Green

Lego background #266
 Noise  CC 0

Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.

Source Firkin

Decorative divider 192 #2503
 Dark  CC 0

From a drawing in 'Worsborough; its historical associations and rural attractions', Joseph Wilkinson, 1879.

Source Firkin

Background pattern purple #1998
 Colorful  CC 0

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

Source Firkin