Light and tiny, just the way you like it.
Source Rohit Arun Rao
Medium gray fabric pattern with 45-degree lines going across.
Source Atle Mo
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
From a drawing in 'At home', J. Sowerby, J. Crane and T. Frederick, 1881.
Source Firkin
Like the name suggests, this background image consists of a pattern of dark bricks. It may be an option for you, if you are looking for something that looks like a brick wall for use as a background on web pages. It's not a masterpiece, but looks pretty nice when is tiled.
Source V. Hartikainen
Remixed from a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
The tile this fill pattern is based on can be had by using shift+alt+i on the rectangle.
Source Firkin
Lovely pattern with splattered vintage speckles.
Source David Pomfret
Number five from the same submitter, makes my job easy.
Source Dima Shiper
CC0 and a seamless pattern from a tile drawn in Paint.net .
Source SliverKnight
Prismatic Groovy Concentric Background 3 No Black
Source GDJ
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Tile available in Inkscape using shift-alt-i on the selected rectangle
Source Firkin
Prismatic Hypnotic Pattern No Background
Source GDJ
Derived from an image that was uploaded to Pixabay by Kaz
Source Firkin
Dark Tile-able Grunge Texture. I think this texture can be classified as grunge. It's free and seamless, as always.
Source V. Hartikainen
Coming in at 666x666px, this is an evil big pattern, but nice and soft at the same time.
Source Atle Mo
The act or state of corrugating or of being corrugated, a wrinkle; fold; furrow; ridge.
Source Anna Litvinuk
Dark, lines, noise, tactile. You get the drift.
Source Anatoli Nicolae
From a drawing in 'Cassell's Library of English Literature', Henry Morley, 1883.
Source Firkin
Light and tiny, just the way you like it.
Source Rohit Arun Rao
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne
Fix and cc0 to get the tile this is based on.
Source SliverKnight
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso