This one is so simple, yet so good. And you know it. Has to be in the collection.
Source Gluszczenko
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Abstract Arbitrary Geometric Background derived from an image on Pixabay.
Source GDJ
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
A seamless striped fabric-like texture colored in a dark reddish brown color.
Source V. Hartikainen
Zero CC tileable dry grass texture, photographed and made by me. CC0
Source Sojan Janso
Prismatic Geometric Pattern Background 2
Source GDJ
The tile this is formed from can be retrieved in Inkscape by selecting the rectangle and using shift+alt+i
Source Firkin
I love the movie Pineapple Express, and I’m also liking this Pineapple right here.
Source Audee Mirza
A seamlessly tile-able grunge background image.
Source V. Hartikainen
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Clover with background for St. Patrick's Day. Add to a card with a doily, ribbon, a leprechaun or other embellishments.
Source BAJ
Formed by distorting an image on Pixabay that was uploaded by gustavorezende. To get the tile this is based on, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
A dark striped seamless pattern suitable for use as a background on websites.
Source V. Hartikainen
Actually, there's no clouds in it, but I think it looks quite nice.
Source V. Hartikainen
More Japanese-inspired patterns, Gold Scales this time.
Source Josh Green
It’s like Shine Dotted’s sister, only rotated 45 degrees.
Source mediumidee
A series of 5 patterns. That’s what the P stands for, if you didn’t guess it.
Source Dima Shiper
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Dark pattern with some nice diagonal stitched lines crossing over.
Source Ashton
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Abstract Ellipses Background Grayscale
Source GDJ
A free background image with a seamless texture of cardboard. This texture of cardboard looks quite realistic, especially when is actually tiled.
Source V. Hartikainen