Nothing like a clean set of bed sheets, huh?
Source Badhon Ebrahim
This one is super crisp at 2X. Lined paper with some dust and scratches.
Source HQvectors
Prismatic Groovy Concentric Background 4
Source GDJ
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Crossing lines with a subtle emboss effect on a dark background.
Source Stefan Aleksić
Abstract Ellipses Background Grayscale
Source GDJ
A background tile of dark textile. Made this a long time ago and just now decided to publish it.
Source V. Hartikainen
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Simple gray checkered lines, in light tones.
Source Radosław Rzepecki
No idea what Nistri means, but it’s a crisp little pattern nonetheless.
Source Markus Reiter
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A free seamless background image with abstract texture of green "curtain".
Source V. Hartikainen
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne