More Textures
Green Fibers@2X #92
 Dark  CC BY-SA 3.0

The green fibers pattern will work very well in grayscale as well.

Source Matteo Di Capua

Colorful Floral Background@2X #480
 Noise  CC 0

Colorful Floral Background

Source GDJ

Leafy pattern (colour) #2334
 Fabric  CC 0

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

Source Firkin

Noisy@2X #46
 Paper  CC BY-SA 3.0

Looks a bit like concrete with subtle specks spread around the pattern.

Source Mladjan Antic

"Brown Stone", Seamless Web Texture #1030
 Stone  CC BY-SA 3.0

This background texture resembles stone. It may be used as a background on web pages or on some of their html elements (header, borders, menu bar, etc.). Just modify it for your needs.

Source V. Hartikainen

Wine Cork@2X #34
 Light  CC BY-SA 3.0

Wine cork texture based off a scanned corkboard.

Source Atle Mo

Always Grey@2X #54
 Dark  CC BY-SA 3.0

Crossing lines with a subtle emboss effect on a dark background.

Source Stefan Aleksić

Iron Grip #587
 Dark  CC BY-SA 3.0

Sounds like something from World of Warcraft. Has to be good.

Source Tony Kinard