To get the repeating unit, select the rectangle in Inkscape and use shift+alt+i
Source Firkin
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
I love these crisp, tiny, super subtle patterns.
Source Badhon Ebrahim
A seamless paper background colored in pale yellow.
Source V. Hartikainen
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
Prismatic Rounded Squares Grid 4 No Background
Source GDJ
Classic vertical lines, in all its subtlety.
Source Cody L
This is a semi-dark pattern, sort of linen-y.
Source Sagive SEO
Zero CC tileable seed texture, edited by me to be seamless from a Pixabay image. CC0
Source Sojan Janso
8 by 8 pixels, and just what the title says.
Source pixilated
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless pattern the starting point for which was a 'rainbow twist' texture in Paint.net.
Source Firkin
Prismatic Abstract Line Art Pattern Background
Source GDJ
A dark metal plate with an embossed grid pattern and a bit of rust. Here's a dark metal plate texture for use as a tiled background on web pages.
Source V. Hartikainen
Submitted as a black pattern, I made it light and a few steps more subtle.
Source Andy
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
A seamless pattern based on a square tile that can be retrieved in Inkscape by selecting the rectangle and using shift-alt-i.
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
A bit of scratched up grayness. Always good.
Source Dmitry
A rusty grunge background for websites. Feel free to use it in your site's theme.
Source V. Hartikainen
A topographic map like this has actually been requested a few times, so here you go!
Source Sam Feyaerts
Derived from a drawing in 'The Murmur of the Shells', Samuel Cowen, 1879.
Source Firkin
Used in small doses, this could be a nice subtle pattern. Used on a large surface, it’s dirty!
Source Paul Reulat
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin