More Textures
Green Fibers #91
 Dark  CC BY-SA 3.0

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

Source Matteo Di Capua

Greek key pattern 5 #2294
 Dark  CC 0

Seamless pattern made from a tile that can be obtained in Inkscape by selecting the rectangle and using shift+alt+i.

Source Firkin

White Texture@2X #132
 Light  CC BY-SA 3.0

Not the most creative name, but it’s a good all-purpose light background.

Source Dmitry

Rocky Wall@2X #42
 Light  CC BY-SA 3.0

High detail stone wall with minor cracks and specks.

Source Projecteightyfive

Wallpaper Tile 13 #240
 Light  CC 0

An abstract Background pattern of purple twisty patterns.

Source TikiGiki

Background pattern 221 #2347
 Dark  CC 0

A seamless pattern formed from a tile made from ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Seamless Paper Texture (Pale Yellow) #1217
 Yellow  CC BY-SA 3.0

A seamless paper background texture colored in pale yellow. This seamless texture is ideal for those who need a yellow background image for their website. The texture resembles paper.

Source V. Hartikainen

Retro Circles Background 7 #431
 Unknow  CC 0

Retro Circles Background 7

Source GDJ

Background pattern 227 (colour 6) #2309
 Red  CC 0

A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.

Source Firkin

White Sand #19
 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