People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
New paper pattern with a slightly organic feel to it, using some thin threads.
Source Atle Mo
An abstract texture of water. It's not perfect, but will do. You may download if you like it.
Source V. Hartikainen
This is the remix of "Tileable Wave Pattern 2" uploaded by "Arvin61r58".Thanks.I added a wire-mesh fence seamless pattern as a lower layer.
Source Yamachem
Smooth Polaroid pattern with a light blue tint.
Source Daniel Beaton
A repeating graphic with ancient pattern. I came up with this name/title at last minute, so you may find that there is very little of ancientness in this pattern after all.
Source V. Hartikainen
In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
Prismatic Geometric Pattern Background No Black
Source GDJ
Used the 6th circle pattern designed by Viscious-Speed to create a print that can be used for card making or scrapbooking. Save as a PDF file for the best printing option.
Source Lovinglf
I scanned a paper coffee cup. You know, in case you need it.
Source Atle Mo
Vector version of a png that was uploaded to Pixabay by pencilparker
Source Firkin
This is the remix of "Colorful Floral Pattern Background 3" uploaded by "GDJ". Thanks.
Source Yamachem
From a drawing in 'Az Osztrák-Magyar Monarchia irásban és képben', 1885.
Source Firkin
Super detailed 16×16 tile that forms a beautiful pattern of straws.
Source Pavel
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
You may use it as is, or modify it as you like.
Source V. Hartikainen
A seamless pattern based on a rectangular tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Remixed from a drawing in 'The March of Loyalty', Letitia MacClintock, 1884.
Source Firkin
You don’t see many mid-tone patterns here, but this one is nice.
Source Joel Klein
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Remixed from a drawing in 'Maidenhood; or, the Verge of the Stream', Laura Jewry, 1876.
Source Firkin
Prismatic Abstract Geometric Background 5 No Black
Source GDJ