Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed 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
Remixed from a design seen in 'Burghley. The Life of William Cecil', William Charlton, 1857
Source Firkin
A good starting point for a cardboard pattern. This would work well in a variety of colors.
Source Atle Mo
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Design drawn in Paint.net, vectorised using Vector Magic and finished in Inkscape.
Source Firkin
Formed from a tile based on a drawing from 'Viaggi d'un artista nell'America Meridionale', Guido Boggiani, 1895.
Source Firkin
Classy golf-pants pattern, or crossed stripes if you will.
Source Will Monson
It looks like a polished stone surface to me. Download it for free, as always.
Source V. Hartikainen
White little knobs, coming in at 10x10px. Sweet!
Source Amos
Spice up your next school project with this icon background.
Source Swetha
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
A grayscale fabric pattern with vertical lines of stitch holes.
Source V. Hartikainen
An alternative colour scheme to the original seamless pattern.
Source Firkin
Light and tiny, just the way you like it.
Source Rohit Arun Rao
A seamless gray background texture suitable for use on websites. To me, it has the look of stone. Feel free to modify it to meet your needs (by making it a bit lighter or darker, for example).
Source V. Hartikainen
Just to prove my point, here is a slightly modified dark version.
Source Atle Mo
Embossed lines and squares with subtle highlights.
Source Alex Parker
From a design found in 'History of the Virginia Company of London; with letters to and from the first Colony, never before printed', Edward Neill, 1869.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
From a drawing in 'Two Women in the Klondike', Mary Hitchcock, 1899.
Source Firkin
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra