Background pattern 339 #1709
 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

 More Textures
Orange Gingham Checkered Background #258
 Stripes  CC 0

From PDP.

Source GDJ

Shapes pattern #2409
 Brown  CC 0

A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

Inflicted #117
 Grid  CC BY-SA 3.0

Dark squares with some virus-looking dots in the grid.

Source Hugo Loning

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

Prismatic Groovy Concentric Background 2@2X #454
 Noise  CC 0

Prismatic Groovy Concentric Background 2

Source GDJ

Darth Stripe@2X #100
 Dark  CC BY-SA 3.0

Diagonal lines with a lot of texture to them.

Source Ashton

Zig-zag pattern #2418
 Grid  CC 0

A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.

Source Firkin

Japanese family crest called chidori 02 #2440
 Brown  CC 0

The image depicts a seamless pattern of a Japanese family crest called "chidori" in Japanese .A chidori in Japanese means a plover in English.

Source Yamachem

Seamless Wood Pattern #889
 Wood  CC BY-SA 3.0

A seamlessly repeating background pattern of wood. The image is procedurally generated, and, I think, it's turned out quite well.

Source V. Hartikainen

Background pattern pink and colours #2032
 Colorful  CC 0

A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.

Source Firkin

Retro Squares Background 4 #418
 Dark  CC 0

Retro Squares Background 4

Source GDJ

Transparent Square Tiles #298
 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

Background pattern 306 (colour 5) #1879
 Colorful  CC 0

Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.

Source Firkin

Starring@2X #586
 Dark  CC BY-SA 3.0

If you need stars, this is the one to get.

Source Agus Riyadi