Drawn in Paint.net using the kaleidoscope plug-in and vectorised.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Derived from an image that was uploaded to Pixabay by mdmelo.
Source Firkin
It almost looks a bit blurry, but then again, so are fishes.
Source Petr Šulc
Prismatic Geometric Pattern Background 2
Source GDJ
The image depicts meshed silhouettes of various things.The original image is an OCAL clipart called "Enter FOSSASIA 2016 #IoT T-shirt Design Contest" uploaded by "openclipart".Thanks.
Source Yamachem
Embossed lines and squares with subtle highlights.
Source Alex Parker
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
Light and tiny, just the way you like it.
Source Rohit Arun Rao
White circles connecting on a light gray background.
Source Mark Collins
A pattern formed from a squared tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
Sort of like the Photoshop transparent background, but better!
Source Alex Parker
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Prismatic Abstract Geometric Background 4
Source GDJ
Three shades of gray makes this pattern look like a small carbon fiber surface. Great readability even for small fonts.
Source Atle Mo
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Looks a bit like concrete with subtle specks spread around the pattern.
Source Mladjan Antic
Tiny circle waves, almost like the ocean.
Source Sagive
A seamless pattern formed from a square tile. The tile can be retrieved by selecting the rectangle in Inkscape and using shift-alt-I.
Source Firkin
Might not be super subtle, but quite original in its form.
Source Alex Smith
Run a restaurant blog? Here you go. Done.
Source Andrijana Jarnjak
A light background pattern with diagonal stripes. Here's a simple light striped background for you.
Source V. Hartikainen