Background pattern pink #1954
 Pink  CC 0

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

Source Firkin

 More Textures
Diamond pattern 2 (colour 5) #2264
 Blue  CC 0

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

Source Firkin

Merely Cubed #589
 Grid  CC BY-SA 3.0

Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.

Source Etienne Rallion

Background pattern 230 (colour 2) #2302
 Green  CC 0

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

Source Firkin

Old Wall #346
 Wall  CC BY-SA 3.0

Old concrete wall in light shades.

Source Bartosz Kaszubowski

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

Diagmonds #336
 Dark  CC BY-SA 3.0

Love the style on this one, very fresh. Diagonal diamond pattern. Get it?

Source INS

Background pattern 230 (colour 3) #2303
 Green  CC 0

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

Source Firkin

Background pattern 225 (colour 3) #2325
 Pink  CC 0

Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

Diamond pattern (colour 9) #2269
 Fabric  CC 0

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

Source Firkin

Background pattern 8 (black) #209
 Dark  CC 0

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

Source Firkin

Prismatic Groovy Concentric Background 3 #457
 Noise  CC 0

Prismatic Groovy Concentric Background 3

Source GDJ

Seamless Core Pattern 6 #170
 Dark  CC 0

Seamless Core Pattern 6

Source GDJ

Decorative divider 198 #2437
 Dark  CC 0

From a drawing in 'Codogno e il suo territorio nella cronaca e nella storia'', Gio and Giarella Cairo, 1897.

Source Firkin

Batthern #324
 Grid  CC BY-SA 3.0

Sometimes simple really is what you need, and this could fit you well.

Source Factorio.us Collective