Here's a repeatable texture that resembles a light green concrete wall or something similar.
Source V. Hartikainen
Wild Oliva or Oliva Wilde? Darker than the others, sort of a medium dark pattern.
Source Badhon Ebrahim
Seamless , tileable CC-0 texture. Created by my own, feel free to use wherever you want!
Source Linolafett
A chequerboard pattern with a fruit theme. The fruits are from a posting by inkscapeforum.it.
Source Firkin
Tiny circle waves, almost like the ocean.
Source Sagive
Zero CC tillable hard cover red book with X shape marks. Scanned and made by me.
Source Sojan Janso
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Seamless pattern the tile for which can be had by using shift-alt-I on the selected rectangle in Inkscape.
Source Firkin
If you need a green background for your blog/website, try this one. Remember that Green Striped Background is seamlessly tileable.
Source V. Hartikainen
Because I love dark patterns, here is Brushed Alum in a dark coating.
Source Tim Ward
Inspired by a pattern found in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Some dark 45 degree angles creating a nice pattern. Huge.
Source Dark Sharp Edges
Not a flat you live inside, like in the UK – but a flat piece of cardboard.
Source Appleshadow
ZeroCC tileable beechwood wood texture, generated in Neo Texture Edit by me. CC0
Source Sojan Janso
You can never get enough of these tiny pixel patterns with sharp lines.
Source Designova
Inspired by a drawing in 'Poems', James Smith, 1881.
Source Firkin
Prismatic Isometric Cube Wireframe Pattern No Background
Source GDJ
Got some felt in my mailbox today, so I scanned it for you to use.
Source Atle Mo
A seamless dark leather-like background texture with diagonal lines that look like stitches.
Source V. Hartikainen
Geometric lines are always hot, and this pattern is no exception.
Source Listvetra
Colorful Floral Background No Black
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen