You may use it as is, or modify it as you like.
Source V. Hartikainen
The classic 45-degree diagonal line pattern, done right.
Source Jorick van Hees
Fix and cc0 to get the tile this is based on.
Source SliverKnight
Everyone needs some stardust. Sprinkle it on your next project.
Source Atle Mo
Seamless Prismatic Geometric Pattern With Background
Source GDJ
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From a drawing in 'Cowdray: the history of a great English House', Julia Roundell, 1884.
Source Firkin
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Colour version of the original seamless pattern.
Source Firkin
Not so subtle. These tileable wood patterns are very useful.
Source Elemis
Sounds French. Some 3D square diagonals, that’s all you need to know.
Source Graphiste
A light brushed aluminum pattern for your pleasure.
Source Tim Ward
Derived from a drawing in 'Historiske Afhandlinger', Adolf Jorgensen, 1898.
Source Firkin
A white version of the very popular linen pattern.
Source Ant Ekşiler
Number five from the same submitter, makes my job easy.
Source Dima Shiper