Prismatic Arrows Background #392
 Noise  CC 0

Prismatic Arrows Background

Source GDJ

 More Textures
Colourful background #2010
 Colorful  CC 0

Made by distorting a simple pattern using the 'sin waves' plugin for Paint.net and vectorising in Vector Magic

Source Firkin

Background pattern 18 #202
 Dark  CC 0

A seamless pattern the starting point for which was a 'colour modulo' texture in Paint.net.

Source Firkin

Dark Brown Leather Texture, Seamless Tile #1092
 Leather  CC BY-SA 3.0

The texture of this background image has some similarities with leather, and it's colored in a dark brown color. So, if you are looking for a dark brown background image for your website, this may be an option for you.

Source V. Hartikainen

Seamless Prismatic Geometric Pattern With Background #264
 Dark  CC 0

Seamless Prismatic Geometric Pattern With Background

Source GDJ

Background pattern 315 #1845
 Blue  CC 0

The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin

Background pattern 201 (colour 4) #2494
 Grid  CC 0

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

Source Firkin

Prismatic Dots Background 3 #505
 Noise  CC 0

Prismatic Dots Background 3

Source GDJ

Background pattern 263 #2073
 Pink  CC 0

Actually remixed from a pattern on Pixabay. But then noticed a very similar one on Openclipart.org uploaded by btj51q2.

Source Firkin

Prismatic Geometric Pattern Background #407
 Noise  CC 0

Prismatic Geometric Pattern Background

Source GDJ

Black And White Floral Pattern Background Inverse #197
 Dark  CC 0

Black And White Floral Pattern Background from PDP.

Source GDJ

Brushed Alum Dark@2X #66
 Dark  CC BY-SA 3.0

Because I love dark patterns, here is Brushed Alum in a dark coating.

Source Tim Ward