Not even 1kb, but very stylish. Gray thin lines.
Source Struck Axiom
Prismatic Curved Diamond Pattern 8 No Background
Source GDJ
A heavy dark gray base, some subtle noise and a 45-degree grid makes this look like a pattern with a tactile feel to it.
Source Atle Mo
A playful triangle pattern with different shades of gray.
Source Dimitrie Hoekstra
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i
Source Firkin
Semi-light fabric pattern made out of random pixels in shades of gray.
Source Atle Mo
Number 2 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
A seamless pattern formed from a tile that can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
Plywood Web Background background image for use in web design.
Source V. Hartikainen
To get the tile this is based on select the rectangle in Inkscape and use shift+alt+i.
Source Firkin
An alternative colour scheme to the original seamless pattern.
Source Firkin
Derived from a drawing in 'Historiske Afhandlinger', Adolf Jorgensen, 1898.
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
The following orange background pattern resembles a honeycomb.
Source V. Hartikainen
Inspired by a pattern I saw in a 19th century book. This seamless pattern was created from a square tile. To get the tile, select the pattern in Inkscape and use shift+alt+i.
Source Firkin
Horizontal and vertical lines on a light gray background.
Source Adam Anlauf
Colorful Floral Background No Black
Source GDJ
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin