Here's a subtle marble-like background for use on websites.
Source V. Hartikainen
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
The square tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Abstract Tiled Background Extended 12
Source GDJ
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Element of beach pattern with background.
Source Rones
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Heavy depth and shadows here, but might work well on some mobile apps.
Source Damian Rivas
A nice and simple gray stucco material. Great on its own, or as a base for a new pattern.
Source Bartosz Kaszubowski
Remixed from a design on Pixabay. To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Here's an yet another seamless note paper texture for use as a background on websites.
Source V. Hartikainen
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
ZeroCC tileable wood boards texture, photographed and made by me. CC0
Source Sojan Janso
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
A free tileable background colored in off-white (antique white) color.
Source V. Hartikainen