If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
From a drawing in 'Friend or Fortune? The story of a strange year', Robert Overton, 1897.
Source Firkin
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Light square grid pattern, great for a “DIY projects” sort of website, maybe?
Source Rafael Almeida
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A seamless pattern based on a rectangular tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
The classic notebook paper with horizontal stripes.
Source Are Sundnes
Prepared mostly as a raster in Paint.net and vectorised.
Source Firkin
Pattern produced in Paint.net using the Vibrato plug-in.
Source Firkin
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
From a drawing in 'Real Sailor-Songs', John Ashton, 1891.
Source Firkin
Prismatic Chevrons Pattern 5 With Background
Source GDJ
Prismatic Geometric Tessellation Pattern 2 No Background
Source GDJ