A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Classy golf-pants pattern, or crossed stripes if you will.
Source Will Monson
Derived from elements found in a floral ornament drawing on Pixabay.
Source Firkin
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
These dots are already worn for you, so you don’t have to.
Source Matt McDaniel
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
A rusty grunge background for websites. Feel free to use it in your site's theme.
Source V. Hartikainen
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim
From drawing in 'Musings in Maoriland', Thomas Bracken, 1890.
Source Firkin
Prismatic Chevrons Pattern 5 With Background
Source GDJ
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
From a drawing in 'Uit de geschiedenis der Heilige Stede te Amsterdam', Yohannes Sterck, 1898.
Source Firkin
On a large canvas you can see it tiling, but used on smaller areas, it’s beautiful.
Source Paul Phönixweiß
Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
Prismatic Abstract Background Design No Black
Source GDJ
8 by 8 pixels, and just what the title says.
Source pixilated
A grid of squares with green colours. Since the colours are randomly distributed it is automatically seamless.
Source Firkin
A free seamless background image with abstract texture of green "curtain".
Source V. Hartikainen
Kaleidoscope Prismatic Abstract No Background
Source GDJ
This one has rusty dark brown texture.
Source V. Hartikainen
Prismatic Abstract Geometric Background 4 No Black
Source GDJ
Remixed from a drawing in 'Some account of the Worshipful Company of Ironmongers', John Nicholl, 1866.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin