A free seamless background image with abstract texture of green "curtain".
Source V. Hartikainen
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
Background Wall, Art Abstract, Star Well & CC0 texture.
Source Ractapopulous
Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
A cute x, if you need that sort of thing.
Source Juan Scrocchi
The rectangular tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A free green background pattern with a pattern of rhombuses on a seamless texture. Feel free to use it as a tiled background image on your web site.
Source V. Hartikainen
A background formed from an image of an old tile on the New York Metropolitan Museum of Art website. To get the base tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Nice little grid. Would work great as a base on top of some other patterns.
Source Arno Gregorian
Bit of a strange name on this one, but still nice. Tiny gray square things.
Source Carlos Valdez
Prismatic Abstract Geometric Background derived from an image on Pixabay.
Source GDJ
Prismatic Abstract Geometric Background 5 No Black
Source GDJ
As far as fabric patterns goes, this is quite crisp.
Source Heliodor Jalba
Derived from an image that was uploaded to Pixabay by starchim01
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
More bright luxury. This is a bit larger than fancy deboss, and with a bit more noise.
Source Viszt Péter
Remixed from a raster on Pixabay that was uploaded by ArtsyBee.
Source Firkin
This is a more minute version of "fishnet 01".The image depicts a seamless pattern of a fishnet with a plenty of fish.It may be a lucky charm for fishermen.
Source Yamachem
Same as gray sand but lighter. A sandy pattern with small light dots, and some angled strokes.
Source Atle Mo
Prismatic Hexagonalist Pattern No Background
Source GDJ
Could be paper, could be a Polaroid frame – up to you!
Source Chaos
Prismatic Abstract Line Art Pattern Background
Source GDJ