As far as fabric patterns goes, this is quite crisp.
Source Heliodor Jalba
Prismatic Rounded Squares Grid 4 No Background
Source GDJ
A seamless pattern formed from a tile made from ornament 22. To get the tile, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
From a drawing in 'Art Embroidery', M.S. Lockwood and E. Glaister, 1878.
Source Firkin
Background formed from the iconic plastic construction bricks that gave me endless hours of fun when I was a lad.
Source Firkin
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
More tactile goodness. This time in the form of some rough cloth.
Source Bartosz Kaszubowski
The image depicts a Japanese Edo pattern called "kanoko or 鹿の子" meaning "fawn" which has a fur with small white spots.
Source Yamachem
A seamless textured paper for backgrounds. Colored in pale orange hues.
Source V. Hartikainen
You know you can’t get enough of these linen-fabric-y patterns.
Source James Basoo
Light gray grunge wall with a nice texture overlay.
Source Adam Anlauf
This beige background pattern resembles a concrete wall with engravings or something similar to it.
Source V. Hartikainen
Prismatic Hexagonalist Pattern No Background
Source GDJ
Zero CC tileable pine bark texture, photographed and made by me. CC0
Source Sojan Janso
Prismatic Polyskelion Pattern No Background
Source GDJ
You know I’m a sucker for these. Well-crafted paper pattern.
Source Mihaela Hinayon
In the spirit of WWDC 2011, here is a dark iOS inspired linen pattern.
Source Atle Mo
Remixed from a raster on Pixabay, that was uploaded by ArtsyBee.
Source Firkin
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
A repeating background with seamless texture of stone. There haven't been any stone-like backgrounds for a while, so I have decided to create one more. The rest can be found in the appropriate category.
Source V. Hartikainen
Colored maple leaves scattered on a surface. This is tileable, so it can be used as a background or wallpaper.
Source Eady
Prismatic Abstract Geometric Background 2 No Black
Source GDJ
The classic subtle pattern. Sort of wall/brick looking. Or moon-looking?
Source Joel Klein
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
White handmade paper pattern with small bumps.
Source Marquis
This background texture resembles stone. It may be used as a background on web pages or on some of their html elements (header, borders, menu bar, etc.). Just modify it for your needs.
Source V. Hartikainen
Zero CC tileable Laminate wood texture, photographed and made by me. CC0
Source Sojan Janso