As far as fabric patterns goes, this is quite crisp.
Source Heliodor Jalba
Number 3 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Inspired by a pattern seen on a public domain image of a very old tile. To get the unit cell, select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
Tiny little flowers growing on your screen. Nice, huh?
Source Themes Tube
Seamless pattern formed from a tile that can be had by selecting the rectangle in Inkscape 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
Like the name says, light and gray, with some small dots and circles.
Source Brenda Lay
Zero CC tileable hard cover green book, scanned and made by me. CC0
Source Sojan Janso
Brushed aluminum, in a bright gray version. Lovely 2X as well.
Source Andre Schouten
From a drawing in 'A Life Interest', Mrs Alexander, 1888.
Source Firkin
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
To get the tile this is based on, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
People seem to enjoy dark patterns, so here is one with some circles.
Source Atle Mo
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Here's a bluish gray striped background pattern for use on web sites.
Source V. Hartikainen
The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i
Source Firkin
The file was named striped lens, but hey – Translucent Fibres works too.
Source Angelica
From a drawing in 'Les Chroniqueurs de l'Histoire de France depuis les origines jusqu'au XVIe siècle', Henriette Witt, 1884.
Source Firkin
Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
Sharp diamond pattern. A small 24x18px tile.
Source Tom Neal