Tessellation 16 (colour 5) #2211
 Yellow  CC 0

The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.

Source Firkin

 More Textures
Bird pattern (colour 2) #2292
 Green  CC 0

Utilising a bird from s-light and some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Tileable Wave Pattern 2 remix #2490
 Dark  CC 0

This is the remix of "Tileable Wave Pattern 2" uploaded by "Arvin61r58".Thanks.I added a wire-mesh fence seamless pattern as a lower layer.

Source Yamachem

Abstract Tiled Background Extended 11 #522
 Noise  CC 0

Abstract Tiled Background Extended 11

Source GDJ

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

Ravenna #354
 Wall  CC BY-SA 3.0

I guess this is inspired by the city of Ravenna in Italy and its stone walls.

Source Sentel

Background pattern 308 (colour 6) #1867
 Pink  CC 0

Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.

Source Firkin

Retro Squares Background 2 #416
 Noise  CC 0

Retro Squares Background 2

Source GDJ

Micro Carbon@2X #8
 Carbon  CC BY-SA 3.0

Three shades of gray makes this pattern look like a small carbon fiber surface. Great readability even for small fonts.

Source Atle Mo

Background pattern 9 (greyscale) #213
 Dark  CC BY-SA 3.0

Greyscale version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net

Source Firkin