It’s an egg, in the form of a pattern. This really is 2012.
Source Paul Phönixweiß
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Zero CC tileable pine bark texture, photographed and made by me. CC0
Source Sojan Janso
Dark squares with some virus-looking dots in the grid.
Source Hugo Loning
Sometimes you just need the simplest thing.
Source Fabricio
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Similar to original, but without gaps in between the arrows. This seamless pattern was created from a rectangular tile. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Derived from an image that was uploaded to Pixabay by pugmom40
Source Firkin
Prismatic Curved Diamond Pattern No Background
Source GDJ
Nothing like a clean set of bed sheets, huh?
Source Badhon Ebrahim
Not the most creative name, but it’s a good all-purpose light background.
Source Dmitry
Remixed from a drawing in 'In an Enchanted Island', William Mallock, 1892.
Source Firkin
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Snap! It’s a pattern, and it’s not grayscale! Of course you can always change the color in Photoshop.
Source Atle Mo
Remixed from a drawing in 'The Canadian horticulturist', 1892
Source Firkin
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A free grid paper background pattern for using on web sites.
Source V. Hartikainen
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett