Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
To get the tile this is formed from select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
This is the third pattern called Dark Denim, but hey, we all love them!
Source Brandon Jacoby
Background pattern originally a PNG drawn in Paint.net
Source Firkin
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape and using shift-alt-i.
Source Firkin
Inspired by a 1930s wallpaper pattern I saw on TV.
Source Firkin
This is a semi-dark pattern, sort of linen-y.
Source Sagive SEO
A subtle shadowed checkered pattern. Increase the lightness for even more subtle sexiness.
Source Josh Green
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Used in small doses, this could be a nice subtle pattern. Used on a large surface, it’s dirty!
Source Paul Reulat
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Prismatic Geometric Pattern Background
Source GDJ
Light honeycomb pattern made up of the classic hexagon shape.
Source Federica Pelzel
A re-make of the Gradient Squares pattern.
Source Dimitar Karaytchev