Used correctly, this could be nice. Used in a bad way, all hell will break loose.
Source Atle Mo
Kaleidoscope Prismatic Abstract No Background
Source GDJ
Submitted by DomainsInfo – wtf, right? But hey, a free pattern.
Source DomainsInfo
A light background pattern with diagonal stripes. Here's a simple light striped background for you.
Source V. Hartikainen
It has waves, so make sure you don’t get sea sickness.
Source CoolPatterns
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'Hundert Jahre in Wort und Bild', S. Stefan, 1899.
Source Firkin
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
You could get a bit dizzy from this one, but it might come in handy.
Source Dertig Media
Prismatic Curved Diamond Pattern 6 No Background
Source GDJ
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Zero CC Mossy stone tileable texture, photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Black & white version of a pattern that came out of playing with the 'light rays' plug-in for Paint.net
Source Firkin
This reminds me of Game Cube. A nice light 3D cube pattern.
Source Sander Ottens
Lovely pattern with splattered vintage speckles.
Source David Pomfret
Tiny little fibers making a soft and sweet look.
Source Badhon Ebrahim
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A seamless canvas texture for using as background on websites. Colored in pale tones of brown.
Source V. Hartikainen
Number 2 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
More in the paper realm, this time with fibers.
Source Jorge Fuentes
Remixed from a drawing in 'A Girl in Ten Thousand', Elizabeth Meade, 1896.
Source Firkin
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
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