To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A dark striped seamless pattern suitable for use as a background on websites.
Source V. Hartikainen
Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A fun-looking elastoplast/band-aid pattern. A hint of orange tone in this one.
Source Josh Green
If you like it a bit trippy, this wave pattern might be for you.
Source Ian Soper
Derived from an image that was uploaded to Pixabay by pugmom40
Source Firkin
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
Prismatic Groovy Concentric Background
Source GDJ
Prismatic Basic Pattern 2 No Background
Source GDJ
A seamless background of warped stripes on paper.
Source V. Hartikainen
From a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
A seamless marble-like texture colored in light blue.
Source V. Hartikainen
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Zero CC tileable Crackled Cement (streaks) texture, photographed and made by me. CC0
Source Sojan Janso
I love the movie Pineapple Express, and I’m also liking this Pineapple right here.
Source Audee Mirza
Have you wondered about how it feels to be buried alive? Here is the pattern for it.
Source Hendrik Lammers
This texture looks like old leather. It should look great as a background on web pages.
Source V. Hartikainen
You know you love wood patterns, so here’s one more.
Source Richard Tabor
Prismatic Groovy Concentric Background 5
Source GDJ