Prismatic Basic Pattern 2 No Background@2X #448
 Noise  CC 0

Prismatic Basic Pattern 2 No Background

Source GDJ

 More Textures
Noisy #45
 Paper  CC BY-SA 3.0

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

Source Mladjan Antic

Sakura Blossoms Background #389
 Noise  CC 0

Sakura Blossoms Background

Source GDJ

Concrete Wall 2@2X #80
 Wall  CC BY-SA 3.0

A light gray wall or floor (you decide) of concrete.

Source Atle Mo

Prismatic Dots Background 6@2X #512
 Dark  CC 0

Prismatic Dots Background 6

Source GDJ

Carbon Fiber Big@2X #327
 Carbon  CC BY-SA 3.0

Bigger is better, right? So here you have some large carbon fiber.

Source Factorio.us Collective

Smooth Wall@2X #28
 Light  CC BY-SA 3.0

Some rectangles, a bit of dust and grunge, plus a hint of concrete.

Source Atle Mo

Background pattern 259 #2133
 Red  CC 0

Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Beige Paper@2X #84
 Paper  CC BY-SA 3.0

This was submitted in a beige color, hence the name. Now it’s a gray paper pattern.

Source Konstantin Ivanov

Background pattern 277 #2029
 Dark  CC 0

A background pattern inspired by designs seen in 'Burghley. The Life of William Cecil', William Charlton, 1857.

Source Firkin

Rice Paper #338
 Paper  CC BY-SA 3.0

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

Source Atle Mo