Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Remixed from a drawing in 'Analecta Eboracensia', Thomas Widdrington, 1897.
Source Firkin
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
A pattern formed from a photograph of a 16th century ceramic tile.
Source Firkin
Background Wall, Art Abstract, Blue Well & CC0 texture.
Source Ractapopulous
A monochrome pattern from a tile that can be had by selecting the rectangle in Inkscaope and using shift+alt+i
Source Firkin
Prismatic Polka Dots Mark II No Background
Source GDJ
Zero CC tileable dry grass texture, photographed and made by me. CC0
Source Sojan Janso
This is so subtle you need to bring your magnifier!
Source Carlos Valdez
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Carbon fiber is never out of fashion, so here is one more style for you.
Source Alfred Lee
A version without colours blended together to give a different look.
Source Firkin
Prismatic Hypnotic Pattern 2 No Background
Source GDJ
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
The starting point for this was a texture drawn with the 'Radial Colors' plug-in in Paint.net.
Source Firkin
Sharp pixel pattern looking like some sort of fabric.
Source Dmitry
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso