Background pattern 309 (colour 3) #1864
 Red  CC 0

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

Source Firkin

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Background pattern 336 (colour 3) #1719
 Blue  CC 0

Formed by distorting the inside front cover of 'Diversæ insectarum volatilium : icones ad vivum accuratissmè depictæ per celeberrimum pictorem', Jacob Hoefnagel, 1630.

Source Firkin

Prismatic Chevrons Pattern 5 With Background #469
 Dark  CC 0

Prismatic Chevrons Pattern 5 With Background

Source GDJ

White Sand@2X #20
 Light  CC BY-SA 3.0

Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.

Source Atle Mo

Repeating Website Background (Blue Gray) #1192
 Concrete  CC BY-SA 3.0

The following repeating website background is colored in a blue gray color and resembles a concrete wall or something similar to it.

Source V. Hartikainen

Prismatic Curved Diamond Pattern 8 No Background@2X #550
 Dark  CC 0

Prismatic Curved Diamond Pattern 8 No Background

Source GDJ

Felt #300
 Wall  CC BY-SA 3.0

Got some felt in my mailbox today, so I scanned it for you to use.

Source Atle Mo

Seamless Core Pattern 4 #168
 Dark  CC 0

Seamless Core Pattern 4

Source GDJ

Sine wave background 2 #1734
 Dark  CC 0

The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin

Green Gobbler@2X #86
 Dark  CC BY-SA 3.0

Luxurious looking pattern (for a T-shirt maybe?) with a hint of green.

Source Simon Meek

Dark Denim@2X #373
 Dark  CC BY-SA 3.0

Thin lines, noise and texture creates this crisp dark denim pattern.

Source Marco Slooten