Retro Circles Background 8@2X #436
 Dark  CC 0

Retro Circles Background 8

Source GDJ

 More Textures
Padded@2X #62
 Dark  CC BY-SA 3.0

A beautiful dark padded pattern, like an old classic sofa.

Source Chris Baldie

Background pattern 251 #2167
 Dark  CC 0

To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Dark Brick Wall@2X #136
 Wall  CC BY-SA 3.0

Black brick wall pattern. Brick your site up!

Source Alex Parker

Lined Paper #362
 Stripes  CC BY-SA 3.0

The classic notebook paper with horizontal stripes.

Source Are Sundnes

3px Tile #342
 Dark  CC BY-SA 3.0

Tiny dark square tiles with varied color tones.

Source Gre3g

Dark Denim@2X #30
 Dark  CC BY-SA 3.0

A dark denim looking pattern. 145×145 pixels.

Source Atle Mo

Prismatic Polka Dots Mark II No Background #530
 Noise  CC 0

Prismatic Polka Dots Mark II No Background

Source GDJ

Background pattern black #2028
 Dark  CC 0

Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857. The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Polonez Pattern@2X #335
 Gray  CC BY-SA 3.0

A car pattern?! Can it be subtle? I say yes!

Source Radosław Rzepecki

Floral design 90 #1815
 Dark  CC 0

From a drawing in 'Hubert Montreuil, or the Huguenot and the Dragoon', Francisca Ouvry, 1873.

Source Firkin

Rice Paper 2@2X #341
 Paper  CC BY-SA 3.0

One can never have too few rice paper patterns, so here is one more.

Source Atle Mo

Background pattern 223 (colour 4) #2350
 Pink  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

Gray Sand@2X #18
 Dark  CC BY-SA 3.0

A dark gray, sandy pattern with small light dots, and some angled strokes.

Source Atle Mo

"Polished Stone", Gray Background Pattern #1053
 Stone  CC BY-SA 3.0

A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).

Source V. Hartikainen