The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Might not be super subtle, but quite original in its form.
Source Alex Smith
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
This is the remix of "Background pattern 115" uploaded by "Firkin".Thanks.
Source Yamachem
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Super simple but very nice indeed. Gray with vertical stripes.
Source Merrin Macleod
Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Don’t look at this one too long if you’re high on something.
Source Luuk van Baars
The classic subtle pattern. Sort of wall/brick looking. Or moon-looking?
Source Joel Klein
Remixed from a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin
Prismatic Geometric Pattern Background 2 No Black
Source GDJ
Prismatic Snowflakes Pattern 2 No Background
Source GDJ
ZeroCC tileable moss texture, photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'Line and form', Walter Crane, 1914.
Source Firkin