More Textures
Ravenna@2X #355
 Wall  CC BY-SA 3.0

I guess this is inspired by the city of Ravenna in Italy and its stone walls.

Source Sentel

Batthern@2X #325
 Grid  CC BY-SA 3.0

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

Source Factorio.us Collective

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

Diagonal lines with a lot of texture to them.

Source Ashton

Tessellation 15 (colour) #2222
 Blue  CC 0

The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.

Source Firkin

"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

Prismatic Abstract Geometric Background 2 No Black@2X #446
 Noise  CC 0

Prismatic Abstract Geometric Background 2 No Black

Source GDJ

Background Patterns - Aubergine #247
 Fabric  CC 0

If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117

Source Viscious-Speed

Background pattern 239 #2218
 Dark  CC 0

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

Source Firkin

Tactile Noise@2X #6
 Dark  CC BY-SA 3.0

A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.

Source Atle Mo

Background pattern 238 (colour 2) #2228
 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 #2327
 Colorful  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

Background pattern 104@2X #562
 Dark  CC 0

Background pattern 104

Source Firkin