The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
Everyone loves a diamond, right? Make your site sparkle.
Source AJ Troxell
Prismatic Groovy Concentric Background 2
Source GDJ
A pattern derived from part of a fractal rendering in Paint.net.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Prismatic Snowflakes Pattern No Background
Source GDJ
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
An alternative colour scheme to the original seamless pattern.
Source Firkin
Prismatic Triangular Background Design Mark II 5
Source GDJ
Looks as if it's spray painted on the wall. You can be sure that this pattern will seamlessly fill your backgrounds on web pages.
Source V. Hartikainen
A seamless background drawn in Paint.net and vectorised with Vector Magic. The starting point was a photograph of drinking straws from Pixabay.
Source Firkin
You guessed it – looks a bit like cloth.
Source Peax Webdesign
This is so subtle: We’re talking 1% opacity. Get your squint on!
Source Atle Mo
Square design drawn in Paint.net and vectorized in Vector Magic.
Source Firkin
White circles connecting on a light gray background.
Source Mark Collins
Continuing the geometric trend, here is one more.
Source Mike Warner
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin