The classic notebook paper with horizontal stripes.
Source Are Sundnes
Black And White Floral Pattern Background Inverse
Source GDJ
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
Prismatic Hypnotic Pattern No Background
Source GDJ
Prismatic Hexagonalism Pattern No Background
Source GDJ
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
A seamless background pattern with impressed gray dots.
Source V. Hartikainen
A dark metallic background with a pattern of stamped dots. Here's a dark "metallic" background pattern for you.
Source V. Hartikainen
Prismatic Basic Pattern 2 No Background
Source GDJ
Prismatic Groovy Concentric Background 5
Source GDJ
Element of beach pattern with background.
Source Rones
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
From a drawing in 'Artists and Arabs', Henry Blackburn, 1868
Source Firkin
A pale olive green background with a seamless texture.
Source V. Hartikainen
Hey, you never know when you’ll need a bird pattern, right?
Source Pete Fecteau
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
Fabric-ish patterns are close to my heart. French Stucco to the rescue.
Source Christopher Buecheler
Love me some light mesh on a Monday. Sharp.
Source Wilmotte Bastien
Here I have tried to create something that would look like maple wood. Not sure how well it's turned out, but at least it looks like wood.
Source V. Hartikainen
If you want png files of this u can download them here : viscious-speed.deviantart.com/gallery/27635117
Source Viscious-Speed
Used in small doses, this could be a nice subtle pattern. Used on a large surface, it’s dirty!
Source Paul Reulat
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso