8 by 8 pixels, and just what the title says.
Source pixilated
A seamless pattern from a tile drawn in Paint.net and vectorised in Vector Magic
Source Firkin
Black paper texture, based on two different images.
Source Atle Mo
Based from Design Kindle
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
I scanned a paper coffee cup. You know, in case you need it.
Source Atle Mo
Cubes as far as your eyes can see. You know, because they tile.
Source Jan Meeus
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
Here's a quite bright pink background pattern for use on websites. It doesn't look like a real fur, but it definitely resembles one.
Source V. Hartikainen
Remixed from a drawing that was uploaded to Pixabay by DavidZydd
Source Firkin
Wild Oliva or Oliva Wilde? Darker than the others, sort of a medium dark pattern.
Source Badhon Ebrahim
Scanned some rice paper and tiled it up for you. Enjoy.
Source Atle Mo
One can never have too few rice paper patterns, so here is one more.
Source Atle Mo
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
This one is rather fun and playful. The 2X could be used at 1X too!
Source Welsley
Remixed from a design seen on Pixabay. The basic tile can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
From a drawing in 'Resa i Afrika, genom Angola, Ovampo och Damaraland', P. Moller, 1899.
Source Firkin
Background Wall, Art Abstract, Block Well & CC0 texture.
Source Ractapopulous
A dark pattern made out of 3×3 circles and a 1px shadow. This works well as a carbon texture or background.
Source Atle Mo