Concrete Wall #77
 Wall  CC BY-SA 3.0

Dark blue concrete wall with some small dust spots.

Source Atle Mo

 More Textures
Retina Dust #915
 Light  CC BY-SA 3.0

First pattern tailor-made for Retina, with many more to come. All the old ones are upscaled, in case you want to re-download.

Source Atle Mo

My Little Plaid #332
 Light  CC BY-SA 3.0

Repeating squares overlapping.

Source Pete Fecteau

Background pattern brown #1951
 Brown  CC 0

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

Source Firkin

Transparent Square Tiles@2X #299
 Grid  CC BY-SA 3.0

The first pattern on here using opacity. Try it on a site with a colored background, or even using mixed colors.

Source Nathan Spady

Prismatic Polyskelion Pattern No Background #394
 Light  CC 0

Prismatic Polyskelion Pattern No Background

Source GDJ

Background pattern 258 #2135
 Dark  CC 0

Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.

Source Firkin

Tessellation 14 variant 1 #2530
 Grid  CC 0

A seamless pattern formed from a modified version of rwwgub's tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Floral Pattern Background 3 #218
 Noise  CC 0

PDP

Source GDJ

Prismatic Hypnotic Pattern 2 No Background@2X #574
 Noise  CC 0

Prismatic Hypnotic Pattern 2 No Background

Source GDJ

Parquet flooring pattern #2427
 Red  CC 0

A seamless pattern recreated from an image on Pixabay. It is reminiscent of parquet flooring and is formed from a square tile, which can be recovered in Inkscape by selecting the ungrouped rectangle and using shift-alt-I together.

Source Firkin

Diamond pattern (colour 2) #2284
 Green  CC 0

From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Background pattern 250 (colour) #2171
 Yellow  CC 0

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

Source Firkin

Elegant Grid #316
 Wall  CC BY-SA 3.0

This is a hot one. Small, sharp and unique.

Source GraphicsWall