Background pattern 306 (colour 6) #1878
 Colorful  CC 0

Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.

Source Firkin

 More Textures
Background pattern 227 (colour 2) #2313
 Blue  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

Colourful background #2007
 Colorful  CC 0

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

Source Firkin

Prismatic Abstract Geometric Background 2 #268
 Noise  CC 0

Prismatic Abstract Geometric Background 2

Source GDJ

Double Lined@2X #52
 Stripes  CC BY-SA 3.0

Horizontal and vertical lines on a light gray background.

Source Adam Anlauf

Background pattern 249 #2179
 Blue  CC 0

To get the tile this is made up from select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Background pattern 105@2X #564
 Dark  CC 0

A seamless pattern formed from background pattern 102

Source Firkin

Rice Paper@2X #339
 Paper  CC BY-SA 3.0

Scanned some rice paper and tiled it up for you. Enjoy.

Source Atle Mo

Cubes #133
 Light  CC BY-SA 3.0

This reminds me of Game Cube. A nice light 3D cube pattern.

Source Sander Ottens

Background pattern 252 (colour 6) #2157
 Light  CC 0

Recreated from a pattern found in 'Az Osztrák-Magyar Monarchia irásban és képben', 1882. To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.

Source Firkin

Prismatic Geometric Pattern Background 2 No Black #410
 Noise  CC 0

Prismatic Geometric Pattern Background 2 No Black

Source GDJ

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

Prismatic Abstract Geometric Background 2 No Black

Source GDJ